Topics

136

Textile Engineering / Waterproof breathable fabrics

« on: June 29, 2015, 04:47:45 PM »

Waterproof breathable fabrics:


Waterproof fabric completely prevents the penetration and absorption of liquid water.

Breathable fabric is actively ventilated and it passively allows water vapor to diffuse through them yet prevents the penetration of liquid water.

Waterproof breathable fabrics resist water droplets from passing through while at the same time allowing water vapor through. The breathability of almost all waterproof breathable fabrics is very dependent upon weather conditions, especially temperature and humidity. Waterproof breathable fabrics are widely used in sportswear and similar Application.
                       
Measurement of breathability

Breathability is measured by the rate at which water vapor passes through in the units of grams of water vapor per square meter of fabric per 24 hours period (g/m2/d), often abbreviated to just ‘g’.
In recent years some of the sporting goods manufacturers have begun including this information on their labels. Typical mid-range fabric tends to have values of 5000 mm of water resistance and 5000g of breathability.

Thanks
Asit Ghosh
Senior lecturer
Dept. of Textile Engineering
Faculty of Engineering, DIU

137

Be a Leader / Steve Jobs Quotes Serve as Valuable Life Lessons

« on: June 29, 2015, 04:40:36 PM »

1. Your time is limited, so don’t waste it living someone else’s life. Don’t be trapped by dogma – which is living with the results of other people’s thinking. Don’t let the noise of others’ opinions drown out your own inner voice. And most important, have the courage to follow your heart and intuition.

2. Sometimes when you innovate, you make mistakes. It is best to admit them quickly, and get on with improving your other innovations.

3. It’s hard to tell with these Internet startups if they’re really interested in building companies or if they’re just interested in the money. I can tell you, though: If they don’t really want to build a company, they won’t luck into it. That’s because it’s so hard that if you don’t have a passion, you’ll give up.”


 Thanks
Asit Ghosh
Senior Lecturer
Dept. of Textile Engineering
Daffodil International University

138

Higher Education / পিএইচডি ফান্ডের জন্য আবেদন বিষয়ক তথ্য

« on: June 28, 2015, 09:36:17 PM »

পিএইচডি ফান্ডের জন্য আবেদন বিষয়ক তথ্য:

বিজ্ঞানী গাট্রুড বি এলিয়ন (Elion) পিএইচডির জন্য ১৫টি আবেদন করেছিলেন। তাঁর দুর্ভাগ্য যে, একটি আবেদনেরও সাড়া পাননি। আত্মপ্রত্যয়ী এই মানুষটিই ১৯৮৮ সালে চিকিৎসাবিজ্ঞানে নোবেল পেয়েছেন। এমন উদাহরণ আরও দেওয়া যাবে। অর্জনের পথটাই কণ্টকাকীর্ণ। সেখানে চেষ্টাই সম্বল। সুতরাং আপনি যদি পিএইচডি ফান্ডের জন্য আবেদন করে ক্লান্ত হয়ে যান, গা ঝারা দিয়ে এখনই আবার শুরু করুন।
অধ্যাপকদের মেইল করছেন কিন্তু তারা উত্তর দিচ্ছেন না, তাই তো? অথবা, উত্তর দিলেও বলছেন, কোনো ফান্ড নেই, পজিশন নেই। এটা খুবই সাধারণ চিত্র! এমনটি আপনার, আমার, সবার ক্ষেত্রেই হচ্ছে। হয়তো দু-একজনের ক্ষেত্রে ভিন্ন। তাহলে কী করা যায়? আবেদনের সময় কিছুটা কৌশলী হয়ে দেখা যেতে পারে। যা অনেকের ক্ষেত্রেই কাজে দিয়েছে। হয়তো আপনার জন্যও সহায়ক হবে।
ক) গণহারে সকল অধ্যাপকদের একই মেইল পাঠানো বন্ধ করুন। অভিজ্ঞ অধ্যাপক এগুলো সহজেই বুঝতে পারেন। ফলে এসব মেইল পড়েন না।
খ) আপনার প্রফেশনাল-প্রাতিষ্ঠানিক মেইল আইডি থাকলে সেটা ব্যবহার করুন (gmail, yahoo ইত্যাদি নয়। এসব আইডির মেইল তাঁরা খুব গুরুত্ব দেন না। কখনো কখনো এসব মেইল ওপেনও করেন না)।
গ) যে অধ্যাপকের গ্রুপে আবেদন করবেন, সে গ্রুপের গবেষণার বিষয়বস্তু (Research Focus/Field) সময় দিয়ে পড়ুন। খুব ভালো হয় সাম্প্রতিক প্রকাশিত আর্টিকেল পড়লে।
ঘ) অনেক সময় তার সাম্প্রতিক প্রকাশিত আর্টিকেল পড়ে তাকে ধন্যবাদ দিতে পারেন। আর ধন্যবাদ দেওয়ার মাধ্যমেই গবেষণা কাজটির প্রশংসা করে দু-একটি প্রশ্ন (যৌক্তিক ও আকর্ষণীয়) করতে পারেন। উল্লেখ করতে পারেন যে, আপনি এই বিষয়টি ভালো বোঝেন ও এ বিষয়ে কাজের আগ্রহ অনেক। যোগাযোগের সূচনা এভাবেও করা যেতে পারে।

ঙ) রিসার্চ প্রপোজাল লিখতে হলে, একটি গবেষণা গ্রুপের সাম্প্রতিক প্রকাশিত আর্টিকেল পড়ে সেই আলোকে কিছু করতে চাওয়ার প্রস্তাব দেওয়াই উত্তম। প্রতিটি মানুষ তার সৃষ্টিকর্মে মোহিত (Obsessed)। যে যে বিষয়ে কাজ করে সেটার ওপর প্রপোজাল লিখুন। প্রপোজাল ১-২ পৃষ্ঠার বেশি না করাই উত্তম। গুরুত্বপূর্ণ ডায়াগ্রাম, ফিগার ব্যবহার করতে হবে বেশি করে। সেখান থেকেই যেন এক-নজরে বোঝা যায় কী বুঝাতে চাচ্ছেন।
প্রতীকী ছবি। সংগৃহীতচ) মেইল আকারে বড় লিখবেন না। মেইলের সঙ্গে প্রয়োজনীয় তথ্যাদি এটাচ করে দেওয়াই উত্তম। ফাইলের জন্য পিডিএফ ফর্ম ব্যবহার করা ভালো।
ছ) আপনার পাবলিকেশন থাকলে সিভিতে সেগুলোই আগে উল্লেখ করুন। পাবলিকেশনের সঙ্গে DOI (Digital Object Identifier) নাম্বার দিন। সেটা থাকলে আর্টিকেল খুঁজে পাওয়া খুব সহজ (https://dx. doi. org/)। (যদি আপনার আর্টিকেলের DOI নাম্বার না থাকে, তাহলে সেটা আন্তর্জাতিক মানের আর্টিকেল নয়।জ) একজন অধ্যাপক আপনার সম্পর্কে খুঁটিনাটি জানতে চাইবেন। ফলে সে পরিচিতদের কাছ থেকে আপনার ব্যাপারে শুনতে চায়। সে জন্য রেফারেন্স লেটার গুরুত্বপূর্ণ। বাইরে রেফারেন্স লেটার হয় গোপনীয় (Confidential)। আমাদের দেশে সবাইকে একটি করে হাতে দিয়ে দেওয়া হয় (আমাদের দেশে সব ছাত্রই অত্যন্ত মেধাবী ও রাষ্ট্রবিরোধী কাজ থেকে বিরত)। চেষ্টা করুন তুলনামূলক পরিচিত গবেষকের কাছ থেকে রেফারেন্স লেটার নিতে।

ঝ) আপনার থিসিস থাকলে সেই থিসিস থেকে একটি অ্যাবস্ট্রাক্ট তৈরি করুন (এক-দুই পৃষ্ঠা)। বাংলাদেশের এমএস থিসিসের ভলিউম (অন্তত বিজ্ঞানে), পৃথিবীর বহু দেশের পিএইচডি থিসিসের দ্বিগুণ বা ত্রিগুণ। একজন অধ্যাপকের এই থিসিস পড়ার সময় নেই। অধ্যাপক যদি চান, তাহলে পুরো থিসিস পাঠান।
ঞ) মাতৃভাষা ইংরেজি, এমন দেশের অধ্যাপকদের কাছে মেইল লিখতে গেলে ইংরেজির ভাষাগত বিষয়ে সতর্ক থাকা ভালো।
ওপরের বিষয়গুলো আপনার প্রস্তুতির জন্য হয়তো সহায়ক হবে কিন্তু প্রস্তুতিটা আপনাকেই নিতে হবে। শুভ কামনা!


(লেখক ডক্টরাল গবেষক, স্টকহোম বিশ্ববিদ্যালয়, সুইডেন। ই-মেইল: redoxrouf@yahoo.com)

Asit Ghosh
Senior Lecturer
Textile Engineering Department
Daffodil International University

139

Textile Engineering / Safety and health issues in the textile industry(part5)

« on: June 26, 2015, 10:50:58 PM »

Ergonomic issues:

Ergonomic issues are observed in a majority of the units engaged in textile-related activities in India. Most of these units have a working environment that is unsafe and unhealthy for the workers. Workers in these units face a number of problems such as unsuitable furniture, improper ventilation and lighting, and lack of efficient safety measures in case of emergencies. The workers in such units are at risk for developing various occupational diseases. Musculoskeletal disorders like carpal tunnel syndrome, forearm tendinitis, bicapital tendinitis, lower back pain, epicondylitis, neck pain, shoulder pain, and osteoarthritis of the knees are some of the occupational diseases that have been observed among the workers on account of poor ergonomic conditions. These issues are more common in developing nations as compared to developed ones.
 
As per a study by Parimalam Parimalam, Kamalamma N. and Ganguli AK in the year 2006, there is a considerable difference in the heights of the stools and the tables used for various operations such as cutting and ironing. This led to the workers having to sit in an uncomfortable position for entire work days. The stools were not padded in most of the units, leading to increased discomfort on the part of the workers. Moreover, the stools did not have a backrest, as a result of which the workers did not get adequate support to the back. In most of the units, the level of lighting was low and improper placement of lighting fixtures led to low lighting at the point of work, leading to eye strain. On account of the continuous use of irons in some units, the humidity level is very high, contributing to the workers discomfort.


                              .......the end......

140

Nutrition and Food Engineering / Health Benefits of Dates

« on: June 26, 2015, 07:01:10 PM »

A Summary of Dates Health Benefits:
Dates are Great for:

1. Weight loss
2. Relieving constipation, supporting regular bowel movements
3. Promoting heart health, reducing heart disease risk
4. Diarrhea
5. Iron-deficiency anemia
6. Reducing blood pressure
7. Impotence
8. Promoting respiratory and digestive health
9. Pregnancy deliveries
10. Hemorrhoid prevention
11 Chronic conditions such as arthritis
12. Reducing colitis risk
13. Preventing colon cancer

141

Textile Engineering / Safety and health issues in the textile industry(part4)

« on: June 26, 2015, 09:39:31 AM »

Exposure to noise:
High levels of noise have been observed in most of the units engaged in the textile industry, particularly those in developing countries. In the long run, exposure to high noise levels has been known to damage the eardrum and cause hearing loss. Other problems like fatigue, absenteeism, annoyance, anxiety, reduction in efficiency, changes in pulse rate and blood pressure as well as sleep disorders have also been noted on account of continuous exposure to noise. Lack of efficient maintenance of machinery is one of the major reasons behind the noise pollution in a majority of the units. Though it causes serious health effects, exposure to noise is often ignored by textile units because its effects are not immediately visible and there is an absence of pain.
 
A study of 77 employees in textile mills in Nagpur was conducted by Ruikar MM, Motghare DD and Vasudeo ND. This study revealed that 76.6% of the employees were at risk for developing noise-induced hearing loss. The study of Indian textile units by R. Steinberg, J. Hannak and K. Balakrishnan indicated that 21.3% of the workers studied suffered from noise-induced hearing loss.

142

Textile Engineering / Safety and health issues in the textile industry(part3)

« on: June 25, 2015, 03:47:36 PM »

Exposure to chemicals:
Workers in the textile industry are also exposed to a number of chemicals, especially those engaged in the activities of dyeing, printing and finishing. Chemicals based on benzidine, optical brighteners, solvents and fixatives, crease-resistance agents releasing formaldehyde, flame retardants that include organophosphorus and organobromine compounds and antimicrobial agents are used in textile operations.
 
Studies have revealed links between exposure to formaldehyde and nasal and lung cancer as well as to brain cancer and leukemia, which can be fatal. In the long run, exposure to formaldehyde could lead to respiratory difficulty and eczema. Contact of the chemicals with skin as well as inhalation of the chemicals can lead to several serious health effects.
 
A study conducted in USA revealed a correlation between the presence of cancer of the buccal cavity and pharynx and occupation in the textile industry. Another study revealed that textile workers were at high risk for developing cancer of the stomach while another study indicated a low degree of correlation between oesophageal cancer and working in the textile industry. Moreover, a high degree of colorectal cancer, thyroid cancer, testicular cancer and nasal cancer was observed among textile workers. Also, a relationship between the presence of non-Hodgkin's lymphoma and working in the textile industry was observed.
 
As per a study conducted on 1300 people working in 'tie and dye' units in Jodhpur and neighboring areas, 100 workers were observed to have occupation-related dermatitis. This constituted 7.69% of the total sample. Red RC base and naphthol were observed to be the most common culprits in this regard.

143

Textile Engineering / Safety and health issues in the textile industry_2nd part

« on: June 25, 2015, 01:44:08 PM »

Exposure to cotton dust: The workers engaged in the processing and spinning of cotton are exposed to significant amounts of cotton dust. They are also exposed to particles of pesticides and soil. Exposure to cotton dust and other particles leads to respiratory disorders among the textile workers. The fatal disease of byssinosis, commonly known as brown lung, is caused among people working in the textile industry on account of excessive exposure to cotton dust. The symptoms of this disease include tightening of the chest, coughing, wheezing and shortness of breath.
 
In the year 1938 in USA, it was estimated that about 35000 people had already been affected by the disease, while 100000 other people were at risk of contracting it. Hence the Occupational Safety and Health Administration i.e. OSHA made it compulsory for employers in the textile industry to protect their workers from over exposure to cotton dust and its evil effects. The OSHA determined certain guidelines which are applicable to all private employers in the US textile industry.
 
OSHA has laid down a Cotton Dust Standard with a view to reducing the exposure of the workers to cotton dust and protecting them from the risk of byssinosis. It has set up Permissible Exposure Limits (PELs) for cotton dust for different operations in the textile industry. This standard has helped bring down the rate of occurrence of byssinosis significantly. Different states might adopt different standards for occupational safety and health; however, in those states where there are no standards fixed by the State, the Federal standards are accepted.
 
For an eight-hour day, the OSHA Cotton standard has been determined at 200 micrograms of cotton dust per cubic meter of air in case of yarn manufacturing, 500 micrograms in case of textile waste houses, 750 micrograms in case of weaving operations, and 1000 micrograms in case of for waste recycling. Employers are required to measure the quantity of respirable cotton dust once in 6 months or whenever there is any change that might lead to a change in the level of dust. If the level of dust in the atmosphere is higher than that as per OSHA guidelines, the management should take measures to reduce the same. As per these guidelines, the employer is required to inform the employees in writing of the dust level present in the atmosphere as well as the steps that the management is planning to take for its reduction. If the dust level cannot be reduced, it is the duty of the management to provide respirators to the employees.

The OSHA Cotton Dust Standard was amended in the year 2000, which exempted a method of washing cotton from the rule.
 
A study conducted by R. Steinberg, J. Hannak and K. Balakrishnan regarding textile units in India revealed that pulmonary function in textile workers decreased significantly with exposure to cotton dust over a long period of time. Another study conducted on textile units in Mumbai, India indicated an 11-33% incidence of chronic bronchitis in textile workers. Another study revealed an increase in the rate of occurrence with an increase in exposure to cotton dust.
 
Studies have revealed that acute respiratory diseases are more common among the children working in carpet weaving units in Jaipur as compared to other children in the same city. The prevalence of respiratory diseases among child textile workers was 26.4%, while it was 15.2% among other children. Experts believe that this is on account of high exposure to cotton dust.

144

Textile Engineering / Safety and health issues in the textile industry

« on: June 25, 2015, 11:11:04 AM »

The textile industry consists of a number of units engaged in spinning, weaving, dyeing, printing, finishing and a number of other processes that are required to convert fibre into a finished fabric or garment. There are several safety and health issues associated with the textile industry. This article aims at studying each of these issues in relation to the US and Indian textile industries in detail, along with the possible solutions for these problems.
 
The major safety and health issues in the textile industry can be stated as under:
1)       Exposure to cotton dust
2)       Exposure to chemicals
3)       Exposure to noise
4)       Ergonomic issues

                                                                                                                             to be continue...

145

English Language Lab / Classical Engllish prefix( Native)

« on: May 09, 2012, 11:29:36 AM »

                                                                            List of English prefixes
      
Native English      
prefix
                                Meaning
               Example

a-   verb > predicative adjective with progressive aspect   afloat, atremble
anti-   against   anti-war, antivirus, anti-human
arch-   supreme, highest, worst   arch-rival, archangel
be-   equipped with, covered with, beset with (pejorative or facetious)   bedeviled, becalm, bedazzle, bewitch
co-   joint, with, accompanying   co-worker, coordinator, cooperation
counter-   against, in opposition to   counteract, counterpart
de-   reverse action, get rid of   de-emphasise
dis-   not, opposite of   disloyal, disagree
dis-   reverse action, get rid of   disconnect, disinformation
en-/em-   to make into, to put into, to get into   enmesh, empower
ex-   former   ex-husband, ex-boss, ex-colleague, exit
fore-   before   forearm, forerunner
in-/il-/im-/ir-   not, opposite of   inexact, irregular
inter-   between, among   interstate, interact
mal-   bad(ly)   malnourish
mid-   middle   midlife
mini-   small   minimarket, mini-room
mis-   wrong, astray   misinformation, misguide
out-   better, faster, longer, beyond   outreach, outcome
over-   too much   overreact, overact
post-   after   post-election, post-graduation
pre-   before   pre-election, pre-enter
pro-   for, on the side of   pro-life
re-   again, back   rerun
self-   self   self-sufficient
step-   family relation by remarriage   stepbrother
trans-   across, from one place to another   transatlantic
twi-   two   twibill, twilight
un-   not, opposite of   unnecessary, unequal
un-   reverse action, deprive of, release from   undo, untie
under-   below, beneath, lower in grade/dignity, lesser, insufficient   underachieve, underground, underpass
up-   greater, higher, or better   upgrade, uplift
with-   against   withstand

146

Textile science, events, trade and issues / clay particle can be used as "Textile coating"

« on: April 10, 2012, 12:26:49 AM »

Clay particle is commonly any of group of important hydrous aluminum silicates with a layer (sheet) structure and very small size, as for example montmorillonite, which are often organically modified to render them organophilic and to enable their dispersion into a polymer. The result of such dispersion is a Nano composite comprised of nanoscale clay particles and a surrounding polymer. Important clay particles are Kaolinite, Illite, Bentonite, Chlorite and Montmorillonite. The most used clay particle in textile coating is Montmorillonite: Chemically (Na, Ca) (Al, Mg)6(Si4O10)3(OH) 6-nH2O, Hydrated Sodium Calcium Aluminum Magnesium Silicate Hydroxide. The aim of this study is to focus on functional properties of nanoclay coated textiles. Nanoclay particle can play an important role in flame retardant textile (cotton or polyester) coating. They can be acted as carriers for drugs, fragrances or other active agents and enable the controlled release of the incorporated species (bacteria, biocidal) which could find applications in skin care products. Recently, clays have become more important for various aspects of environmental science and remediation. Clay particle may absorb various pollutants including organic compounds (such as atrazine, trifluraline, parathion and malathion) and inorganic trace metals (such as copper, zinc, cadmium and mercury) from soils and groundwater which are mostly health hazards. As it is biodegradable and generated from purely nature occurring resources, has very less effect on the environment and human being.

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Science Discussion Forum / Poor wet strength of viscose!!!

« on: April 08, 2012, 12:21:33 PM »

Cotton as a dominating natural fibre imparts a major contribution in the whole textile market including natural and artificial fibers. The demand of this cellulosic fibre is increasing rapidly day by day, on the other hand supply cannot fulfill its demand, and as a result price goes higher in world market. Viscose as cellulosic origin, the cheapest of all cellulosic fibres could be the best alternative. Viscose fibre exhibits some similar properties compared to cotton except its poor wet strength. Some chemical finishes like water repellent and soil release can be used to improve its poor wet strength. Both water repellent and soil release finishes helped in reducing the molecular barrier around the individual fibres that lowered the surface tension of the fibre. It reduces the absorbency of viscose fibre hence leads to higher wet strength. Water repellent and soil release finishes can be applied individually or combinly. This improved property of viscose could replace the cotton fibre in certain applications like bed linen.