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Thursday 21 June 2012
New Sibal plan to make entry into IITs tougher
A compromise formula aimed at breaking the deadlock between teachers and HRD minister Kapil Sibal over admissions to the Indian Institutes of Technology (IITs) could end up hurting hundreds of thousands of aspiring students.
Under the new formula, only the top 20% students in respective class 12 board exams would be eligible for appearing in the IIT entrance exam, top government and IIT sources told HT.
Under the new formula, only the top 20% students in respective class 12 board exams would be eligible for appearing in the IIT entrance exam, top government and IIT sources told HT.
The compromise was brokered by the Prime Minister, who met members of the protesting All India IIT Faculty Federation (AIIFF) last week and asked Sibal to consider their demands.
Sibal had wanted an admission system where the board exam percentile was given weightage along with scores in a screening test while selecting candidates for a second, advanced entrance exam. This process allowed students who scored relatively lower in the boards to make up for it by doing better in the screening test.
But faced with persistent opposition from IIT faculty federations on weightage to board scores, Sibal has asked IIT-Delhi director RK Shevgaonkar to seek the opinion of faculty across the IITs on the compromise plan.
The new proposal, to be discussed by the IIT senates and faculty associations this week, places students in the top 20 percentile of board scores on an equal footing in the selection process.
This would negate Sibal’s intention of encouraging students to focus on their board exams, but rob 80% students of even a chance of trying for the IITs.
Since the class 12 results are unlikely to be declared in time for the two-tier IIT test, all students would need to appear for the exams even if their board marks turn them ineligible later.
Sunday 3 June 2012
IIT-Kanpur academic senate to discuss new proposals on Common Entrance Test
The demand of the members of faculty forum of IIT-Kanpur of convening an urgent meeting of the academic senate to discuss HRD ministry's proposal of making changes in the joint entrance examination and conducting Common Entrance Test (CET) in 2013 for students willing to take admission into IITs, NITs, and IIITs, has been accepted by chairman Sanjay Govind Dhande. The meeting would be held on June 8.
A member of faculty forum said that if other IITs will agree and do what HRD ministry wants, then IIT-Kanpur will conduct its own entrance examination. This issue will be discussed in the senate meeting.
A group of faculty members said all the issues related to the JEE-2013 and CET would be discussed.Some faculty members are against the common entrance test which the HRD ministry wants to conduct in 2013. They are also protesting against the proposed changes in the JEE where the performance candidates in class XII would also be taken into consideration. A total of 40 per cent of a student's performance would be measured through his class XII marks and the remaining would be valued through the JEE.
The teachers are also angry that their suggestions were ignored by the HRD ministry.
Meanwhile, the members of the faculty forum told TOI that they will not accept the common entrance test as recommended by HRD ministry as IITs have their own standards which cannot be at par with other entrance examinations.
The teachers mentioned that IIT council, the apex body for the IITs in the country, would be required to pass an ordinance before the implementation of the new proposals made by HRD ministry.
A member of faculty forum said that if other IITs will agree and do what HRD ministry wants, then IIT-Kanpur will conduct its own entrance examination. This issue will be discussed in the senate meeting.
A group of faculty members said all the issues related to the JEE-2013 and CET would be discussed.Some faculty members are against the common entrance test which the HRD ministry wants to conduct in 2013. They are also protesting against the proposed changes in the JEE where the performance candidates in class XII would also be taken into consideration. A total of 40 per cent of a student's performance would be measured through his class XII marks and the remaining would be valued through the JEE.
The teachers are also angry that their suggestions were ignored by the HRD ministry.
Meanwhile, the members of the faculty forum told TOI that they will not accept the common entrance test as recommended by HRD ministry as IITs have their own standards which cannot be at par with other entrance examinations.
The teachers mentioned that IIT council, the apex body for the IITs in the country, would be required to pass an ordinance before the implementation of the new proposals made by HRD ministry.
Friday 1 June 2012
IIT aspirants struggle to adjust as new engineering test gets green signal
Students preparing for the newcommon engineering test scheduled for 2013, find themselves struggling to adjust to the new format, under which the earlier neglected board exams are now being given 40% weightage. Apart from other colleges, the Joint Entrance Exam (JEE) is now the sole gateway to the prestigious IITs, for which aspirants start preparing at least two years in advance.
Prince Saluja, a student of Guru Nanak High School and Junior College, has been preparing for the IITs since last year. "I will be appearing for the exam next year and suddenly I am faced with a total change in the pattern. For the last one year, my focus has been on cracking the competitive exam with board exam studies on the back burner. However, with a 40% weightage to the boards in the JEE, I have to now shift gears midway and am afraid that there is not enough time left," said Saluja.
Nisha Kothari owns a coaching centre in the city and feels students have no choice but to change their study approach. "Time management will be the key and students will have to refocus on their board exams as there is no choice. Though at my centre, students are prepared for state board simultaneously, hence it does not become a huge problem, but now that effort has to be greater," said Kothari.
She adds that students who top the popular AIEEE too, score an average of 75%-80% in their board exams, which gives an indication on where their focus is.
Parents too are a worried lot as they apprehend the changes will jeopardize their wards' chances in JEE 2013. Akshay Naik (name changed), said, "My son shifted to the state board in Std XI and took admission at a city college where attendance is not mandatory. He uses that time in studying at the coaching class and practice for the JEE, but now I have to start his tuitions for the state board exam as well. The government has turned every kid who will appear for Std XII next year into guinea pigs for its academic experiment."
Abhishek Bansal, from whose coaching centre this year's city IIT topper came, feels that rural students would lose out in a big way. "By the time the information percolates everywhere, too much time would have been lost. Also in city, one can get access to good tutors who can help with their preparations but that is going to be an uphill task for the rural folks," said Bansal.
Union HRD minister Kapil Sibal will meet state education ministers on June 5 to further discuss the implementation of the JEE.
IIT alumni to move court on changes in JEE
Alumni members of the Indian Institutes of Technology (IITs) are gearing up for a legal recourse on the changes to be introduced in the joint entrance examination with effect from 2013.
IIT Delhi alumni president Somnath Bharti told Business Standard, "We will have a meeting tomorrow at IIT Delhi campus to work out the modalities of which court to approach and decided on the petitioners."
The councils of IITs, NITs (National Institutes of Technology) and IIITs (Indian Institute of Information Technology) on Monday decided to have joint entrance test for engineering colleges from 2013.
The new format would increase dependence on coaching institutes and would be subject to the varying standards of Class XII boards, bringing down the standard of IITs. IITs have technical leadership and by doing this, Kapil Sibal would be jeopardising the vision Nehru had while creating IITs as a centre of excellence, he added
Union HRD Minister Kapil Sibal, who made the announcement after chairing a joint council of IITs, NITs and IIITs, said the selection of the candidates for the IITs and other central institutes would be different even as all the aspirants will have to go through all the steps under new format. This system will replace the IIT-JEE and AIEEE.
The Central Advisory Board of Education (CABE), which meets on June 6 at New Delhi, is expected to pass a resolution to hold common entrance test for all technical educational institutions across the country.
Wednesday 30 May 2012
Possible Selection Criteria for IIT JEE 2013
The Indian Institutes of Technology (IITs) are all set to bring a new change in the pattern for
Joint Entrance Exam (JEE) which was conducted Every year across the country. The changed
exam pattern would be followed from the year 2013.
This is a combine exam of JEE and AIEEE .This is a single exam for entrance in all 13 IITs, 45
NITs, 5 IISc and Colleges under AIEEE.It is expected 150000 student appear for this exam.
The new pattern of JEE might include an aptitude test for the exam aspirants. The students will
have to crack this aptitude test consisting of questions based on reasoning and all other subjects
that the students have studied in their school level. The aptitude test would also include questions
related to subjects like physics, chemistry and maths.
The first part will be Aptitude Test and second part will Test Of Subjects (Physics, Chemistry,
Mathsmatics).
This arrangement has been proposed with an aim to reduce the pressure on the students.Students
have done well in 10+2 if they want to creak higher rank in exam.This step get moved students
towards Schools again.
There are 42 state boards and because of this reason, some kind of uniformity has to be
established to match the performance of the individual students (in their class XII)
with each other.
It is an extremely tough task to bring about uniformity in the percentages secured by the students
in their class XII results as the percentage secured by a student in one state board varies from the
percentage secured by some other student in other state board.
As different states have different boards and there are only two Central boards – CBSE and
ICSE, it will be a difficult task to establish uniformity in the percentages achieved by an
individual student when comparing his performance with the other individuals.
INDIAN SCIENCE- ENGINEERING ELIGIBILITY TEST (ISEET)
Date Of Exam :April / May, 2013
Governing Boby :
CBSE Will Conduct The ISEET-2013 Exam.Under The Direction Of Director IIT
Kanpur,Academic Committe Will Took Eyes On Whole Procedure.
Exam Pattern/Scheme : ISEET Will Divide Into Two Part –
PaperΙ: ISEET – Main | PaperΙΙ: ISEET – Advance
ISEET – Main : ISEET-Main Will Be A Test Of
- Critical Thinking
- Logical Reasoning
- Mantal Ability
ISET – Advance : ISET-Advance Will Be Test Of
– Basic Science And Engineering
– Physice/Chemistry/Maths
Note : Both Paper ISAT-Main And ISET-Advance Will Held On Same Day.60%
Weightage Of ISET Test And 40% Weightage Of ΧΙΙ Will Decide The Rank.
Attention all IIT aspirants!!! From the year 2013, the whole new change will be in IIT JEE exam
pattern. There will be an aptitude test consisting of questions based on reasoning and all other
subjects that you have studied in your schools like physics, chemistry and maths. So Prepare
yourself accordingly if you are preparing for IIT 2013.All the Best!!!
You gain .5/100 points for scoring
1% more in the boards. However, for each 1000 ranks you get more than 1/100 points in the top
5000 rank region(the old IITs cutoff). So JEE is going to play a more decisive role
than the boards, but a 94-95% makes life much easier. Work hard to get at least 88%(90
percentile) in the boards and give your best for JEE. Guys shaping up for a top 500 rank can
afford to get around 85%(don't sue me for this ;) ), but the rest need to be in excess of 90%
to have a fair chance. Note that the percentile vs percentage distribution will change if people
focus more on the boards. So don't take the boards lightly and try to build an advantage before
JEE.
Another fall-out of the new pattern might be a virtual state quota. As the top x% students of each
state will be at the same level, states like Rajasthan, Delhi & AP, which produce most of the
IITians will be at a slight disadvantage as far as the board percentiles are concerned. Even
the CBSE & ICSE boards which tend to have brighter students than the state boards might be
a curse for their students.
As far as student-stress levels are concerned, they are bound to shoot up. Earlier, one would just
focus on JEE, knowing that they had back-up in the form of AIEEE, BITSAT & state exams.
One didn't need to care about the boring board exams and just needed to ensure that they got
more than the qualifying score. Now, one has to work for the boards and prepare for a be all to
end all exam. One bad day and you are in deep trouble. God knows what Sibbal is trying to achieve.
This is only a possible and most likely criteria though no official statement has been given.
Tuesday 29 May 2012
Common admission test will hit rural students
The move of the joint councils of IITs, NITs and IIITs to hold a common admission examination would make it more difficult for students, especially those from rural areas where school infrastructure is poor, Super 30 founder Anand Kumar on Tuesday said.
“If there can be one test for more competitive AIIMS examination, which has fewer seats and more candidates, and IIMs, why can't there be so similar test for IITs,'' Kumar told a news agency.
''The process being adopted is more cumbersome and it will only add more pressure on the students,'' he said.
Anand said the move to implement the common admission examination from 2013 would create confusion among the current batch of students. ''If at all the new system is to be implemented, it should be at least from 2014 so that the students could have enough time to adjust. After all the changes are for the students.''
Maintaining that there was uncertainty still about the mechanism of the proposed two-tier test, he said if JEE-Mains and JEE-Advanced were held the same day it would be psychologically draining for the students.
''More thought needs to be given to the proposed changes before implementing them,'' he added. The proposed reform to bring focus back to the schooling system by giving weightage to performance in Class XII Board examinations normalized on percentile basis would also be a serious challenge, as there is huge gulf between schools of the CBSE and ICSE boards and those under state boards.
The formula to be adopted for percentile calculation is also not clear, as all state boards have different yardsticks, he added.
Anand said the present system would make students more dependent on coaching, as they would require it for three different examinations one for the proposed JEE-Main, another for the proposed JEE-Advanced, which will also have aptitude test and third for scoring high marks in the plus two examinations.
“Students from rural areas who don’t the advantage of quality schooling would miss out from JEE-advanced for no fault of theirs,” he said adding there was need to develop faith in the school system for ensuring better secondary education.
“In fact, the proposed mechanism may work as a deterrent for the rural students dreaming to get into IITs. It would have been appropriate to make a joint admission board comprising IITs, NITs and CBSE for paper setting, evaluation and preparation of the merit list. The IIT council should first arrive at a definite decision and give adequate time to students for transition,” he added.
Anand Kumar's Super 30, set up a decade ago, has been lauded by Time magazine as the best in Asia.
The institute provides free residential coaching to 30 meritorious students from the underprivileged sections of the society and so far 263 students have made it to the IIT's.
Sources and Reference: Zee News, India Today
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Monday 28 May 2012
Common entrance test for engineering, fee hike at IITs likely by 2013
The council of IITs today proposed a pan-India common entrance test for admission to engineering programmes possibly from 2013.
After a five-hour meeting of the council, Human Resource Development Minister Kapil Sibal, said , "We have decided there shall be one exam. Subject to the clearance of the Central Advisory Board of Education (CABE) committee and subject to the clearance of the state ministers we will try and put that into operations from 2013."
The government had constituted a committee under Secretary to the department of science and technology T Ramasami to examine implementation of a single entrance test. Six options were deliberated upon for the test and Ramasami has been asked to finalise one of these
within a month.
On the issue of hiking tuition fee as recommended by the Anil Kakodkar committee, Mr Sibal made it clear that "fee would remain the same at Rs. 50,000 per annum" but added a student,
excluding STs and OBCs, would 'pay back' the amount which is the difference between the fee deposited and what the IIT spends on him.
The cost factor for an IIT for each students at present stands at around Rs. 8 lakh against Rs. 2 lakh paid over the entire duration of the B. Tech programme. The HRD Minister said implementation of the Kakodkar committee recommendation, which had sought to raise the tuition fee to Rs. 2 lakh per annum, was "not possible" with interest of all sections of the society kept in mind.
Mr Sibal said that the 'pay back' scheme won't be applicable to those who enroll into M. Tech programme, those who do PhD and to even those who are recruited as faculty in IIT.The Finance Ministry's nod would be sought before putting in effect the scheme, Mr Sibal said.
On changes in the admission process based on the common entrance test, Mr Sibal said an all-India merit list will be prepared based on the combined weightage given to class XII exam and to a common entrance test. The test will examine a students logic and non-subject matters. Weightage would be given to the marks obtained in class XII boards after the results are equalised for which Indian Statistical Institute will put in place a mathematical formula for equalisation.
The minister said the council was aware of the problems that states like Andhra Pradesh faced while implementing the equalisation procedure. Mr Sibal said Indian Statistical Institute's formula would be based on the data of various boards collected over the past
four years to make it an efficient equalisation model.
The meeting of the council attended by the directors of all IITs took a view of several systems for conduct of the test where it also decided to produce 40,000 PhDs by 2020 and create a pool of 16,000 faculties by then.
Mr Sibal exuded confidence on the viability of the 'pay back' scheme in instalments, saying the DMAT system will be utilised to execute the plan. DMAT is a process for the establishment of a national database of academic qualifications -- currently underway -- in an electronic format by an identified, registered depository. The dematerialisation of certificates would ensure confidentiality, authenticity and fidelity, enabling online verification and easy retrieval of academic qualifications.
Common, complicated 2-tier test for IITs, NITs and IIITs
Starting 2013, a joint entrance examination will be held for admission into the central funded engineering institutions such as IITs, NITs and IIITs.
The councils of the IITs, NITs and IIITs on Monday decided to have joint entrance test for engineering colleges that come under these three councils.
According to the decision taken, for the first time, the class XII examinations will count towards entrance. There will be 50 per cent weightage to the class XII examinations and the rest of the 50 per cent to the main test.
As there are many boards that conduct the class XII exams, therefore, the marks will be neutralised on percentlile basis through an appropriate mechanism.
All aspirants will have to appear for a main test and an advanced test, both to be held on the same day. The top 50,000 students in the main test will have their advance papers evaluated for IIT merit positions.
For other colleges apart from IIT, the weightage is: board – 40 per cent, main test – 40 per cent and advance test – 30 per cent.
Earlier, the IITs had resisted having a joint test with other institutions, following which the two tier system was evolved. The IITs though have agreed that if the formula works for the first three years, they may agree to do away with two tier system and have just one exam.
This is the confirmed report by Director of IIT AND NIT'S.
Sources: IBN LIVE, DECCAN CHRONICLE
Thursday 19 January 2012
Dumas Method For Nitrogen Estimation
| Dumas Method |
The Dumas method in analytical chemistry is a method for the quantitative determination of nitrogen in chemical substances based on a method first described by Jean-Baptiste Dumas over a century and a half ago.[1]
An automated instrumental technique has been developed which is capable of rapidly measuring the crude protein concentration of food samples and is beginning to compete with the Kjeldahl method as the standard method of analysis for protein content for some foodstuffs.
General Principles
A sample of known mass is combusted in a high temperature (about 900 oC) chamber in the presence of oxygen. This leads to the release of CO2, H2O and N2. The CO2 and H2O are removed by passing the gasses over special columns that absorb them. The nitrogen content is then measured by passing the remaining gasses through a column that has a thermal conductivity detector at the end. The column helps separate the nitrogen from any residual CO2 and H2O that may have remained in the gas stream. The instrument is calibrated by analyzing a material that is pure and has a known nitrogen concentration, such as EDTA (= 9.59%N). Thus the signal from the thermal conductivity detector can be converted into a nitrogen content. As with the Kjeldahl method it is necessary to convert the concentration of nitrogen in a sample to the protein content, using suitable conversion factors which depend on the precise amino acid sequence of the protein.
Advantages and Disadvantages
Advantages: It is much faster than the Kjeldahl method (under 4 minutes per measurement, compared to 1-2 hours for Kjeldahl). It doesn't need toxic chemicals or catalysts. Many samples can be measured automatically. It is easy to use.
Disadvantages: High initial cost. It does not give a measure of the true protein, since all nitrogen in foods is not in the form of protein. Different proteins need different correction factors because they have different amino acid sequences. The small sample size makes it difficult to obtain a representative sample.
Kjeldahl Method for Nitrogen Estimation
| Kjeldahl Method |
The Kjeldahl method was developed over 100 years ago for determining the nitrogen contents in organic and inorganic substances. Although the technique and apparatus have been modified over the years, the basic principles introduced by Johan Kjeldahl still endure today.
Kjeldahl nitrogen determinations are performed on a variety of substances such as meat, feed, grain, waste water, soil, and many other samples. Various scientific associations approve and have refined the Kjeldahl method, including the AOAC International (formerly the Association of Official Analytical Chemists), Association of American Cereal Chemists, American Oil Chemists Society, Environmental Protection Agency, International Standards Organization, and United States Department of Agriculture.
The Kjeldahl method may be broken down into three main steps: digestion, distillation, and titration.
Method Description:
| Mechanism |
The Kjeldahl method was developed in 1883 by a brewer called Johann Kjeldahl. A food is digested with a strong acid so that it releases nitrogen which can be determined by a suitable titration technique. The amount of protein present is then calculated from the nitrogen concentration of the food. The same basic approach is still used today, although a number of improvements have been made to speed up the process and to obtain more accurate measurements. It is usually considered to be the standard method of determining protein concentration. Because the Kjeldahl method does not measure the protein content directly a conversion factor (F) is needed to convert the measured nitrogen concentration to a protein concentration. A conversion factor of 6.25 (equivalent to 0.16 g nitrogen per gram of protein) is used for many applications, however, this is only an average value, and each protein has a different conversion factor depending on its amino-acid composition. The Kjeldahl method can conveniently be divided into three steps: digestion, neutralization and titration.
The food sample to be analyzed is weighed into a digestion flask and then digested by heating it in the presence of sulfuric acid (an oxidizing agent which digests the food), anhydrous sodium sulfate (to speed up the reaction by raising the boiling point) and a catalyst, such as copper, selenium, titanium, or mercury (to speed up the reaction). Digestion converts any nitrogen in the food (other than that which is in the form of nitrates or nitrites) into ammonia, and other organic matter to C02 and H20. Ammonia gas is not liberated in an acid solution because the ammonia is in the form of the ammonium ion (NH4+) which binds to the sulfate ion (SO42-) and thus remains in solution:
| Organic N + H2SO4 → |
| (NH4)SO4 + H2O + CO4 + other sample matrix byproducts |
| ammonium sulfate | ammonia gas | |
| (NH4)2SO4 + 2NaOH | 2NH3 + Na2SO4 + 2H2O |
TitrationTitration quantifies the amount of ammonia in the receiving solution. The amount of nitrogen in a sample can be calculated from the quantified amount of ammonia ion in the receiving solution.
There are two types of titration—back titration and direct titration. Both methods indicate the ammonia present in the distillate with a color change.
In back titration (commonly used in macro Kjeldahl), the ammonia is captured by a carefully measured excess of a standardized acid solution in the receiving flask. The excess of acid in the receiving solution keeps the pH low, and the indicator does not change until the solution is "back titrated" with base.
ammonia standard
sulfuric acid
acidexcess
ammonium
sulfatesulfuric
acid2NH3 + 2H2SO4
→ (NH4)2SO4 + H2SO4
(no color change)
In direct titration, if boric acid is used as the receiving solution instead of a standardized mineral acid, the chemical reaction is:
ammonia
sulfatemeasured
excess
acidmeasured
sodium
hydroxideammonium
sulfate(NH4)2SO4 + H2SO4 + 2NaOH
→ Na2SO4 + (NH4)2SO4 + 2H2O
(color change occurs)
The boric acid captures the ammonia gas, forming an ammonium-borate complex. As the ammonia collects, the color of the receiving solutions changes.
ammonia
gasboric
acidammonium-
borate complexexcess
boric acidNH3 + H3BO3
→ NH4 + H2BO-3 + H3BO3
(color change occurs)
The boric acid method has the advantages that only one standard solution is necessary for the determination and that the solution has a long shelf life.
ammonium-
borate
complexsulfuric
acidammonium
sulfateboric
acid2NH4 + H2BO-3 + H2SO4 (NH4)2SO4 + 2H3BO3
(color change occurs in reverse)
Calculations:
Where vs and vb are the titration volumes of the sample and blank, and 14g is the molecular weight of nitrogen N. A blank sample is usually ran at the same time as the material being analyzed to take into account any residual nitrogen which may be in the reagents used to carry out the analysis. Once the nitrogen content has been determined it is converted to a protein content using the appropriate conversion factor: %Protein = F� %N.
Description of the method:
The method consists of heating a substance with sulfuric acid, which decomposes the organic substance by oxidation to liberate the reduced nitrogen as ammonium sulfate. In this step potassium sulfate is added to increase the boiling point of the medium (from 337°F to 373°F / 169°C to 189°C). Chemical decomposition of the sample is complete when the medium has become clear and colorless (initially very dark).
The solution is then distilled with sodium hydroxide (added in small quantities) which converts the ammonium salt to ammonia. The amount of ammonia present (hence the amount of nitrogen present in the sample) is determined by back titration. The end of the condenser is dipped into a solution of boric acid. The ammonia reacts with the acid and the remainder of the acid is then titrated with a sodium carbonate solution with a methyl orange pH indicator.
- Apparatus:
Advantages and Disadvantages:
Advantages. The Kjeldahl method is widely used internationally and is still the standard method for comparison against all other methods. Its universality, high precision and good reproducibility have made it the major method for the estimation of protein in foods.
Disadvantages. It does not give a measure of the true protein, since all nitrogen in foods is not in the form of protein. Different proteins need different correction factors because they have different amino acid sequences. The use of concentrated sulfuric acid at high temperatures poses a considerable hazard, as does the use of some of the possible catalysts The technique is time consuming to carry-out.
Applications
The Kjeldahl method's universality, precision and reproducibility have made it the internationally-recognized method for estimating the protein content in foods and it is the standard method against which all other methods are judged. It does not, however, give a measure of true protein content, as it measures nonprotein nitrogen in addition to the nitrogen in proteins. This is evidenced by the 2007 pet food incident and the2008 Chinese milk powder scandal, when melamine, a nitrogen-rich chemical, was added to raw materials to fake high protein contents. Also, different correction factors are needed for different proteins to account for different amino acid sequences. Additional disadvantages, such as the need to use concentrated sulfuric acid at high temperature and the relatively long testing time (an hour or more), compare unfavorably with the Dumas method for measuring crude protein content.
Conversion factors
Conversion factors for common foods range from 6.38 for dairy and 6.25 for meat, eggs, corn (maize) and sorghum to 5.83 for most grains, 5.70 for wheat flour and 5.46 for peanuts.
Total Kjeldahl Nitrogen or TKN is the sum of organic nitrogen, ammonia (NH3), and ammonium (NH4+) in the chemical analysis of soil, water, or wastewater (e.g. sewage treatment plant effluent). To calculate Total Nitrogen (TN), the concentrations of nitrate-N and nitrite-N are determined and added to TKN.
TKN is determined in the same manner as organic nitrogen, except that the ammonia is not driven off before the digestion step.
The original TKN method was developed by the Danish chemist Johan Kjeldahl in 1883. Today, TKN is a required parameter for regulatory reporting at many plants but is also used to provide a means of monitoring plant operations.
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