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Development thinkers of the past and the present as well as several empirical studies have suggested that “Technology has been the single most important source of economic development and growth”. It has regarded as the vehicle for economic expansion and its absence for the decline. One has called attention to the view that “The international balance of technology is as important as the old standbys, ‘the balance of trade’ or ‘the balance of payments’ – and mat be more so.”

The International Scene:

At the international level technology has been transferable from one economy to another, but the transfer has involved a cost that in many countries has been too prohibitive to permit the transfer in response to market conditions. Obviously the technology which is capable of giving a competitive edge or comparative advantage is not given away free.

Secondly, the cost and ease of technology transfer is a function of the gap between the levels of technology in the economies between which the transfer takes place, the time horizon, and the context or the socio-political and economic environment.

Technologies as marketable commodity are continuously being produced and improved to meet the ever-increasing demands off contemporary societies. It is specifically generated for achieving a competitive edge in the international market. Developing countries like Bangladesh mainly export primary goods to the developed countries, while they import mostly manufactured goods with high technology content. While the prices in the international market of the high technology content products have been increasing steadily, the prices of primary products of low technology content have been fluctuating widely.

Near monopoly of the developed countries in science and technology has been given them a position of world dominance. Developing countries have to be content with technology that is the product of development efforts in countries other than theirs. Consequently, technological dependence is an ever growing phenomenon in many of these countries. Thus, technology application poses problems for the developing countries that are not faced by the developed ones. The problems originate from the differences in the socio-economic and technological levels of the country buying a technology and the country producing and selling it. The country which depends on the export of primary commodities is in deep trouble with balance of payment problems. Worse still, the comparative resource advantages of some of the developing countries are in peril without adequate technological development.

Cheap unskilled labour in the developing countries has, in the recent past, been considered a comparative advantage for producing goods in some relatively labour intensive industries. In this context there has been wholesale transfer of certain manufacturing facilities from the developed to the developing countries. But such advantages may be short-lived and may prove to be illusory, because the introduction of new technologies is likely to reduce the need for cheap unskilled labour. Thus, utilization for emerging technologies (such as robotics, computer aided design, computer aided manufacturing and information technology) will significantly reduce the need for subcontracting labour-intensive production to developing countries (such as garment industry, consumer electronics and assembly plants).

Technology has been referred to as a saleable commodity with a price tag attached to it. Another view has been expressed that technology is being marketed between the developed and developing worlds not even as a commercial article but with a modality which has some resemblance to the leasing of land under feudal conditions.

« on: May 22, 2012, 01:37:29 PM »


Bangladesh is a country of 1,47,570 including low and flat land except some hilly regions in the north east and southeast and some high lands in north and north western part and estaurine water surface. Although the country is predominantly a plain surface it is criss-crossed by a very high density of river systems. This gives the country a riverine nature. About 20 million acres are cultivable land and average household farm size is 1.5 acre. Over 58% of people are landless in Bangladesh.

The pressure of population on land is a crucial factor in the management of land resources in the country. Ours is delta region built up by the alluvial soil from the flow of rivers upstream in India and Nepal. This makes our soil highly fertile but in order to balance food population balance introduction of modern techniques caused to loss of fertility. Besides, availability of land becomes a crucial question with time.
The country lacks a comprehensive land use policy emphasizing the most appropriate and productive use of land. The driving force compelling people of Bangladesh to over exploit land are-

1.   High population.
2.   Poverty.
3.   Improper land use.
4.   Absence of land policy.
5.   Ineffective implementation of laws and guidelines.
6.   Unplanned agricultural practices.
7.   Unplanned and unscientific rural infrastructure development.
8.   Increasing urbanization.


The climate of Bangladesh is a subtropical with temperatures from mean maximum 21-380c and mean minimum 11-190c. Annual rainfall ranges from 2000 mm to 3000 mm. The country has mainly four seasons, the winter (December to February), summer (March to May), monsoon (June to September), and autumn (October to November).

Bangladesh has a humid warm climate that is tropical in some regions but lacks the range variability characteristic of nations with a more terrain. The geographical differences are not great but the higher temperature tends to occur in the West and north. Frost is particularly non existent in the country and is not a risk factor in agricultural production. Rainfall, which ranges from 55 to 140 inches on averages annually, is a highly critical risk factor in agricultural production.

Food grains in particular depend on the timely arrival of rains. Tenuous balance between rainfall and cereal production is a central concern of policy makers and government officials. A delay of seven to ten says in the arrival of monsoon rains can have a dramatic impact on the total grain harvest. Floods and draught are common consequences of the extreme weather patterns found in Bangladesh. The level of rainfall tends to decrease from east to west. The heaviest rains occur during the monsoon months from late May to early October. The months from December to March are the driest.

In general, the rainfall and temperature of Bangladesh provides excellent conditions for agricultural production. The year round season’s offers considerable potential for multiple crops of cropping patterns and resources availability can be properly coordinated. Cropping cycles are closely related to the rainfall and climatic patterns. Among the major crops aman rice, jute and to some extent aush rice have production cycles to take advantage of the monsoon rains. Boro rice on the other hand has been developed to follow the heavy rains and required winter irrigations for optimal production. Wheat, potatoes, and most of the oil seeds, spice and vegetable crops, which are also grown during the winter months can benefit from irrigation. But irrigation is not widely applied to these crops.

Bangladesh is predominantly an agricultural country. Its economy mainly depends on agriculture. About 84% of the people live on rural areas and are directly or indirectly engaged on a wide range of agricultural activities. This sector accounts 31.6% of total GDP.

The major challenge to soil and crop scientist as well as farmers is to maintain sufficient moisture to satisfy plant need. Farmers face acute shortage of water during dry season. Most of the surface water sources such as river, pond and tube well get dry and only option left behind then is ground water. The soil is fertile but deficient in nitrogen.
The endowment of human capability, the availability of new technical knowledge, the modern industrial inputs and the system of public and private institutions serving agriculture are also resources of considerable relevance to the process of growth and development in agriculture. Each is necessary element for agricultural development but each one by itself does not ensure development.

So, government and related organizations should take proper step to ensure supply of irrigations, fertilizers, and other facilities.

Science Discussion Forum / Requirements of GLP
« on: May 22, 2012, 01:34:53 PM »
Requirements of GLP

To perform good laboratory practice (GLP) the following requirements are very much essential.

1.   Management requirement.
2.   Technical requirement.

   Management requirements:

            The management requirements are in the following-

1.   Laboratory management system.
2.   Quality system.
3.   Management commitment.
4.   Document control.
5.   Complaints.
6.   Control nonconforming testing and/ or calibration work.
7.   Corrective action.
8.   Preventive action.
9.   Control of records.
10.   Internal audits.
11.   Management review.

   Technical requirements:

               Many factors determine correctness and reliability of the tests and/ or calibrations by a laboratory. These factors include contributions from:

1.   Human factors.
2.   Accommodation and environmental conditions.
3.   Test and calibration methods and method validation.
4.   Selection of methods.
5.   Analytical method validation.
6.   Equipment.
7.   Sampling.
8.   Testing.
9.   Reference standard and reference materials.
10.   Measurement traceability.

Science Discussion Forum / GLP (Good Laboratory Practice)
« on: May 21, 2012, 11:07:12 AM »
              Good Laboratory Practice (GLP) is intended to promote the quality and validity of test data and result. It is a managerial concept covering the organizational process and the conditions under which laboratory studies are planned, performed, monitored, recorded and reported.

              GLP is a system which produces quality standard consistently by the use of some SOP, confirming the standard specification and laboratory equipments validated by trained analysts and well documented.

              GLP embodies a set of principles that provides a framework within which laboratory studies are planned, performed, monitored, recorded, reported and archived. These studies are undertaken to generate data by which the hazards and risks to users, consumers and third parties, including the environment, can be assessed for pharmaceuticals, cosmetics, foods and feed additives and contaminants, novel foods and biocides.

              GLP helps to assure regulatory authorities that the data submitted are a true reflection of the results obtained during the study and can therefore be relied upon when making risk/ safety assessments.

Sports Zone / Fixtures (1st round) of Euro 2012
« on: May 20, 2012, 05:53:45 PM »
Fixtures (1st round) of Euro 2012

Friday 8th June 2012            
Poland   vs   Greece           National Stadium, Warsaw   10:00 PM   
Russia   vs   Czech Republic   Municipal Stadium, Wroclaw   12:45 AM   

Saturday 9th June 2012            
Netherlands   vs   Denmark           Metalist Stadium, Kharkiv   10:00 PM   
Germany   vs   Portugal           Arena Lviv, Lviv                   12:45 AM   

Sunday 10th June 2012            
Spain           vs   Italy                   PGE Arena, Gdarisk           10:00 PM   
Rep of Ireland vs   Croatia           Municipal Stadium, Poznan   12:45 AM   

Monday 11th June 2012         
France   vs   England           Donbass Arena, Donetsk   16:00 PM   
Ukraine   vs   Sweden           Olympic Stadium, Kiev           12:45 AM   

Tuesday 12th June 2012      
Greece   vs   Czech Republic   Municipal Stadium, Wroclaw   10:00 PM   
Poland   vs   Russia           National Stadium, Warsaw   12:45 AM   

Wednesday 13th June 2012            
Denmark   vs   Portugal           Arena Lviv, Lviv                   10:00 PM   
Netherlands   vs   Germany           Metalist Stadium, Kharkiv   12:45 AM   

Thursday 14th June 2012            
Italy     vs   Croatia                   Municipal Stadium, Poznan   10:00 PM   
Spain     vs   Rep of Ireland           PGE Arena, Gdarisk           12:45 AM   

Friday 15th June 2012            
Ukraine   vs   France           Donbass Arena, Donetsk   10:00 PM   
Sweden   vs   England           Olympic Stadium, Kiev           12:45 AM   

Saturday 16th June 2012      
Czech Republic vs   Poland   Municipal Stadium, Wroclaw   12:45 AM   
Greece        vs   Russia   National Stadium, Warsaw   12:45 AM   

Sunday 17th June 2012               
Portugal   vs   Netherlands           Metalist Stadium, Kharkiv   12:45 AM   
Denmark   vs   Germany           Arena Lviv, Lviv                   12:45 AM   

Monday 18th June 2012      
Croatia   vs   Spain                   PGE Arena, Gdarisk           12:45 AM   
Italy           vs   Rep of Ireland   Municipal Stadium, Poznan   12:45 AM   

Tuesday 19th June 2012            
England   vs   Ukraine           Donbass Arena, Donetsk   12:45 AM   
Sweden   vs   France           Olympic Stadium, Kiev           12:45 AM   

« on: May 19, 2012, 03:09:32 PM »
Honor and status of one country depend on her stock of materials and resources. Bangladesh is a very poor country with limited natural resources. But the amount of different kinds of resources is not negligible. In the past under Colonial government no proper attempt was taken to collect the natural resources of Bangladesh and no remarkable geological survey took place among those days. Subsequently a notable amount of mineral resources was discovered which made a sign of bright future in Bangladesh. The main resources of Bangladesh are-

   Agricultural resources
I.   Fertile Land.
II.   Rainfall.

   Water resources.
   Minerals
i.   Natural gas.
ii.   Coal.
iii.   Oil.
iv.   Peat.
v.   Limestone.
vi.   Hard rock.
vii.   Construction sand.
viii.   Gravel.
ix.   Glass sand.
x.   White clay.
xi.   Beach sand.
xii.   Black gold.
   Human resources.
   Forestry.
   Biodiversity.
   Renewable energy resources.

Science Discussion Forum / Antiperspirants & Deodorants
« on: May 18, 2012, 11:08:03 AM »
Antiperspirants and deodorants are used to mask, remove or decrease perspiration odors, prevent their development, or do all of these.

               Fresh perspiration from the clean body has a mild and generally no objectionable odor. Perspiration undergoes considerable change on standing because of bacterial decomposition.
               Body odor emanating from the skin is a natural phenomenon and occurs in almost all men and women if the skin is not frequently cleansed of sweat residues, sebum and bacteria. The natural bacteria flora of the skin is not removed entirely by washing with soap and water, and although the number are reduced, millions of bacterial exist. As the sweat and sebaceous gland ducts are unaffected by washing, they can rapidly multiply and replenish those which are removed by washing. Odor is produced by the breakdown of the organic fraction of sweat and sebum by the natural skin bacteria. The bacteria isolated from the skin can be divided into two groups-

a) Resident- Those bacteria which have their normal habitat on the skin surface or in the glands and ducts.

b) Transient- Those bacteria which are incidentally deposited on the skin from the atmosphere or clothing.

             Both types of bacteria play a good role for body odor. Two types of sweat glands are found in body. They are- a) Eccrine or small gland which occurs all over the body and b) Apocrine or large gland which are found in association with hair follicles and sebaceous glands.

             The eccrine glands open via a thin duct directly on to the surface of the skin while the apocrine glands generally open into a hair follicle. The eccrine glands are true secretory glands producing clear aqueous sweat that assists the regulation of body temperature by evaporation. These glands respond to thermal stimuli and also to reflexes of the central nervous system and hence are responsible for both hot and cold sweating. On the other hand apocrine glands do not respond to thermal stimuli but react promptly to mental stimulation, producing a more concentrated milky sweat, which has characteristic odor of its own. Eccrine sweat is free from bacteria when freshly secreted and becomes contaminated on reaching the skin surface, whereas apocrine sweat is mixed with the rich flora of the sebaceous ducts and hair follicles immediately on secretion.

             Sweat from both types of glands, combined with sebum and epithelical debris on the skin surface provides ideal conditions for bacterial growth, which is left unchecked, fairly rapidly produces odor.

   Odor controlling agents:

            In order to control the objectionable odors of perspiration, it is necessary either to check the flow of excess perspiration or to eliminate its odor, or both. Among the odor controlling agents, the main types are-

o   Antiperspirants and
o   Deodorants.

   Antiperspirants:

              A variety of substances which have astringent action to inhibit the flow of perspiration is called antiperspirants. Astringent action make body tissue contract and stop bleeding.

              Antiperspirant products are marketed as creams, lotions, sticks, powders and spray form. The FDA product and ingredient review panel for over-the-counter antiperspirants (OTC panel) has assigned three classifications to antiperspirants: category 1, safe to use; category 2, does not meet requirements, remove offending materials; category 3, may be marketed while testing continues.

Mechanism of Antiperspirants-

             Antiperspirants narrowing the openings of the sweat ducts and form a keratonic plug in the sweat duct orifice to obstruct the flow of sweat.

Raw materials-

              Salts of metals such as aluminium, iron, chromium, lead, mercury, zinc and zirconium have astringent properties which may be demonstrated by protein precipitation. But some of these produce discoloration and have toxic effect and are not suitable for cosmetic preparation.

             Salts of aluminium and zinc are most commonly used. The astringency of these salts is also dependent on the anion. Sulfate, chloride, chlorhydroxide and phenolsulfonate have been most widely used, although basic formate, lactate, sulfamate and the alums are also found in antiperspirant products.

             The aluminium compound has been most widely used in antiperspirant preparation. Among them aluminium chlorhydroxide complex commonly referred as aluminium chlorhydrate or aluminium chlorhydroxide is widely used. Because it is not irritating or sensitizing to normal skin and cause little or no damage to fabrics. Other compounds that have been used are: basic aluminium bromide, iodide, and nitrate, and basic aluminium hydroxychloride-zirconyl hydroxyl oxychloride, with and without glycine.

             Most of the salts which show good astringent properties have a low pH (2.5-4.2) and causes skin irritation & corrosiveness to fabrics. The pH of such a product may be satisfactorily modified to reduce skin irritation by addition of small amounts of zinc oxide, magnesium oxide, aluminium hydroxide, or triethanolamine.

   Deodorants:

            Since many people who do not perspire excessively are concerned with body odor, a wide variety of products which are deodorant and not antiperspirant have been successively marketed. Since most body odor is the result of bacterial action on perspiration, a satisfactory deodorant product must contain an effective antibacterial agent.

           Many aluminium salts have both astringent and antiseptic properties. So, product containing astringent aluminium salts act as both antiperspirant and deodorant. Compounds of metals other than aluminium have been used in deodorant products. Zinc oxide, zinc peroxide and zinc stearate are mildly astringent and antiseptic and can be used in deodorant powders. Zinc phenosulphonate is also antiseptic and mildly astringent and is useful ingredient of liquid deodorant.

           The bisphenols, particularly hexachlorophene, have been most widely used in deodorant products. The retention of such products on the skin makes them peculiarly effective with repeated use. Other phenolic antibacterials which have been found effective in body deodorants are para-chloro-meta-xylenol (PCMX) and dichloro-meta-xylenol (DCMX). The phenolic odor of these products is objectionable in many products.

Science Discussion Forum / Cleansing cream
« on: May 18, 2012, 11:04:39 AM »
The purpose of a cleansing cream is the removal of facial makeup, surface grime and oil from the face and throat. A properly formulated cleansing cream will quickly and efficiently remove such applied cosmetics as face powder, rouge, foundation bases, cake makeup and lipstick. The large increase in the use of eye cosmetics has created a need for cleansing products specially formulated to remove such makeup.

                Although adequate washing with soap and soft water will perform the same function, a cleansing cream has certain advantages-

   The chemical nature of facial makeup allows more ready removal by a cleansing cream.
   Cleansing cream is specially formulated to dissolve or lift away all the greasy binding materials holding pigments or grime on skin.

              The effects of cleansing creams and other products are up on a specific type of natural skin oil, sebum, which had solidified over the sebaceous or pilosebaceous orifices. These “plaques” were surprisingly resistant to removal by scrubbing with soap and water but they are removed by the use of various cleansing cream.

              A well balanced modern cleansing cream has low irritation factor and will leave an emollient residual film on the skin, which is protective in a dry skin condition. Cleansing preparations specifically designed for oily skin have acquired more importance. These are based on detergent or solvent action or they may be washable. They are designed to remove surface oil and leave a minimum deposit on the skin.

              In addition to the primary function of cleansing, a multipurpose character can be given to a cleansing cream by appropriate formulation. By addition of modifying ingredients such properties as the abilities to soften, lubricate and protect and obtained.

              Water alone a good cleansing agent. Water removes water soluble soils from the skin. The skin surface normally carries a negative electrostatic charge. Many particles, including bacteria, are also negatively charged. In water, these particles are repelled from the skin with resulting cleansing action. For the abnormal skin pus, blood cell, serious exudates and crust are not effectively and efficiently removed by water from skin. So the oily skin requires a solvent or an emulsification process for removal.

              Soap and detergents aid water in emulsifying the oily soils permitting their removal as an emulsion by rinsing with excess water. Solvents such as gasoline and turpentine also remove the oily soils by dissolving them but they leave the skin deficient in natural oils. Mineral oil has solvent action on the oily soils, but its use may leave the skin greasy and it removes completely with a tissue.

              The modern cleansing cream is based on the solvent action of mineral oil on the oils and grease binding either grime or makeup to the skin.

Science Discussion Forum / Face powder and its characteristics
« on: May 18, 2012, 11:03:11 AM »

   Face powder:

              A face powder is basically a cosmetic product that has its prime function is to complement skin color by imparting a velvet like finish. It should also enhance the appearance of the skin by masking the shine due to the secretion of a sebaceous and sweat glands. Face powders both the loose and the cake or pressed powder, is a blend of white pigments, tinted and perfumed.

   Characteristics of face powder:

   The powder must be opaque enough to mask the shine but not so opaque that it imparts a mask like appearance.
   It imparts a smooth velvet-like finish by masking any shine due to the secretion of the sebaceous and sweat glands.
   It must possess reasonably lasting properties in order to avoid the necessity of frequent re-powdering.
   It must be adherent to the skin.
   Reasonably resistant to the mixed secretions of the skin.
   Through intimate contact of its perfume-laden particles over a warm and relatively large area it should disseminate a pleasant odour.

Science Discussion Forum / Application of alkylaromatic compounds
« on: May 17, 2012, 08:24:23 PM »
Alkylaromatic compounds (products of alkylation of benzene, toluene, xylenes etc.) are used as solvents, lubricating oil additives, transformer oil and intermediate for the manufacture of surface active agents and detergents. They are excellent synthetic plasticizers for rubber. Alkylbenzenes can also be used as lubricating greases and lacquer resins.

Alkylated phenols and their derivatives are outstanding antioxidants and stabilizers in lubricating oils, polymers, synthetic fuels and wide variety of oxygen sensitive materials.

2-Alkyl-4-methylphenol upon condensation with formaldehyde readily gives antioxidant of the bisphenol type. 2-Alkyl-4-methylphenol upon further alkylation produces 2,4,6-trialkylated phenol. 2,4- and 2,6-Xylenols also give 2,4,6-trialkylated phenols upon alkylation. These are antioxidants of the monophenol type. These compounds protect polymers, lubricating oils etc. from thermal degradation. The degradation occurs by the radical chain mechanism.
Alkylated phenols and some of their derivatives are effectively used as insecticides, herbicides and bactericides. These are also used as plant growth regulators and antiseptics. Alkylphenols are used as plasticizers for polymeric material, corrosion inhibitors for metals, pour point depressants for transmission fluid. At low temperature fluidity of oil can be increased by alkylphenols.

Alkylphenols also find use in plastic masses and adhesives, in perfume industry, in the manufacture of paints, varnishes and soaps, in dye industry etc. Alkylphenols are intermediates for the manufacture of surfactant and detergents.
Alkylated ortho-, meta- and para- cresols can be utilized as antioxidants and as intermediates in the production of herbicides and surfactant of the non-ionic type. Monoalkylphenols with alkyl groups of 5-8 carbons atoms are strong bactericides while those with longer alkyl groups (up to 8-12 carbon atoms) are valuable intermediates in the synthesis of non-ionic surfactants. Oil soluble thermoplastic resins used in paints, varnishes and adhesive formulations can be produced upon polycondensation of ortho- or para-alkylphenol with formaldehyde. One of the most effective stabilizers is Ionol (4-methyl-2,6-di-tert.-butylphenol), which is produced by the reaction of p-cresol with isobutylene. Upon condensation of o-tert.-butyl-p-cresol with formaldehyde, the outstanding antioxidant-2246 (2,2-methylene-bis-4-methyl-6-tert.-butyl phenol) is produced. Thus antioxidants of the monophenol and bisphenol types are obtained based on the products of alkylation of p-cresol. Trialkylated phenols (products of 2,4-, 2,3-, 2,5-, 2,6-, 3,4- and 3,5-xylenols) are excellent antioxidants. Alkylated chlorophenols are also excellent antioxidants.

Science Discussion Forum / Alkylation and Alkyaromatic compounds
« on: May 17, 2012, 08:17:27 PM »
Alkylation can be described as the addition or insertion of an alkyl group into a molecule. Significant changes in chemical and physical properties can be brought about by alkylation and the process is often considered as a direct means of imparting new qualities to a compound.

Alkylaromatic compounds and their derivatives are industrially significant because of their versatile applications. The products are termed as petrochemicals because they have been produced from raw materials which are based on crude petroleum. In the middle of the 19th century, aromatic compounds were based on coal coking by-products. Later, in the 20th century, crude oil and natural gas became increasingly important as sources of raw materials because their production, transportation and processing were more economical than in the case of coal.

Alkylaromatic compounds and their derivatives have found wide industrial applications in different fields. These compounds are liquid insulators, synthetic lubricating oils, antifreezers, hydraulic fluid, intermediates for detergents etc. They have also found application in rocket engineering, automobile transport, aircraft etc. Halogenated alkyl aromatic compounds are liquid dielectrics and are favored for use in transformers, capacitors, cables, condensers, etc. Production and uses of synthetic fuels, lubricating oils and polymeric materials have been increasing day by day. But these compounds tend to undergo thermal degradation in the presence of heat, light, air, oxygen, ozone etc. Antioxidants are effectively used for their protection against such deterioration. Phenol and their derivatives are the most effective antioxidants and multifunctional stabilizers in such media. Some of the derivatives of phenol exhibit strong herbicidal, bactericidal and insecticidal activities.

Owing to the practical importance of alkylaryl compounds, alkylation process has earned much importance and attention of the scientists since its invention. Consequently alkylation of aromatic compounds with different alkylating agents in the presence of several acidic catalysts was investigated. But reactions of phenols, isomeric cresols and chloroderivatives of phenols with cyclopentyl chloride, tert.-butyl chloride and 2-methylcyclohexanol in the presence of anhydrous aluminium chloride and perchloric acid have not been sufficiently investigated. Thus synthesis of alkylaromatic compounds by the tert.-butylation of phenol, isomeric cresols with tert.-butyl chloride and cycloalkylation of phenol, p-chlorophenol and isomeric cresols with cyclopentyl chloride and 2-methylcyclohexanol will have both industrial and academic values.

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