Semiautomated Method for Total Nitrogen in Fertilizers

1977 ◽  
Vol 60 (4) ◽  
pp. 881-889
Author(s):  
Larry L Wall ◽  
Charles W Gehrke
Keyword(s):  
Total Nitrogen ◽  
Organic Nitrogen ◽  
Relative Difference ◽  
Commercial Fertilizer ◽  
Total Recovery ◽  
System A ◽  
Relative Standard ◽  
Analysis System ◽  
Semiautomated Method ◽  
Cent Nitrogen

Abstract A semiautomated method (SAM) for total nitrogen in fertilizers has been developed which parallels the official first action semiautomated method for crude protein in feeds, 7.B05–7.B11. The SAM is simple, accurate, precise, flexible, rapid, and requires a minimum of laboratory space. Nitrate was reduced and organic nitrogen materials were digested by the sulfuric-salicylic acid chemistry in the block digestor. The nitrogen, as ammonia, in the digestate was determined automatically at the rate of 40 samples/hr with the automated ammonia analysis system. A small amount of CuSO4, (33 mg/sample) as the SAM digestion catalyst gave total recovery of organic nitrogen in fertilizer. Repeated analyses by the SAM and the AOAC official final action comprehensive nitrogen method (CNM) were made on Magruder fertilizer check samples, liquid and suspension fertilizers, and bulk blended commercial fertilizer materials. Average per cent nitrogen in liquid and suspension samples was higher by the SAM than by the CNM when sample weights similar to those for solid fertilizer were used. The precision of the SAM on liquids also agreed closely with that by the CNM. The only limitation of the semiautomated method was for fertilizer samples containing a Cl/NO3 ratio greater than 0.75 w/w. The SAM recoveries on 3 samples with very high Cl/NO3 ratios wert 94.1–99.1% of those by the CNM. Precision was also less than on any other samples. The average per cent nitrogen found for all experimental samples was 14.68 by the SAM and 14.67 by the CNM. The average relative standard deviation (RSD) for all 22 samples was 1.06% by the SAM and 0.74% by the CNM. When 3 samples with high Cl/NO3 ratios (>0.75) were excluded, the average per cent nitrogen was 15.77 (CNM) and 15.81 (SAM); respective RSDs were 0.68 and 0.65% for the SAM and CNM, respectively. A comparison of results on 405 commercial fertilizer samples by both methods showed an average difference (SAM — CNM) of + 0.017% nitrogen and aver age relative difference of 1.23%.

scholarly journals Missouri Automated Nitrogen Method (MANM) for Fertilizers

1972 ◽  
Vol 55 (3) ◽  
pp. 467-480
Author(s):  
Charles W Gehrke ◽  
John S Killingley ◽  
Larry L Wall
Keyword(s):  
Standard Deviation ◽  
Total Nitrogen ◽  
Primary Standard ◽  
Relative Difference ◽  
Automated System ◽  
Urea Nitrogen ◽  
Average Value ◽  
Color Development ◽  
Automated Method ◽  
Relative Standard

Abstract An automated spectrophotometric method, utilizing Technicon AutoAnalyzer modules, has been developed to determine total nitrogen in fertilizers containing only ammoniacal, nitrate , and urea nitrogen. This colorimetric system employs the Berthelot ammoniaphenate- hypochlorite reaction. A homogeneous chromous/titanous reduction system for the automatic reduction of nitrates was interfaced with the digestion unit and color development manifold, resulting in a total nitrogen system for fertilizers with an effective analysis r a t e of 20-25 samples/hr. A new sample retrieval system removes digested samples from the helix. The totally automated system was optimized to obtain t h e highest sensitivity for nitrogen. Data were compared for 458 samples analyzed by the automated method and the comprehensive nitrogen method (CNM), 2.053–2.054. The average difference between the 2 methods (MANM – CNM) was +0.04% nitrogen. The average relative difference was 1.12%. The average value for 140 samples of KNO3 primary standard analyzed by the MANM was 13.84% nitrogen (theoretical content 13.85%). The results of these standards ranged from 13.58 to 14.14% nitrogen and the standard deviation was 0.11%. The relative standard deviation was 0.80%. Of fertilizer samples received for analysis, less than 1% contained insoluble organic nitrogenous material which was unsuitable for analysis by the MANM. These few samples were not included in the statistical evaluation. The MANM is rapid, accurate, and precise and is a convenient and dependable automated method for the determination of total nitrogen in fertilizers containing only ammoniacal, nitrate , and urea nitrogen.

A NEW ORBITAL INTERACTION ANALYSIS SYSTEM "LUMMOX" AND IT'S APPLICATION OF PHOSPHINE-PALLADIUM COMPLEXES

2005 ◽  
Vol 04 (01) ◽  
pp. 345-355 ◽  
Author(s):  
MASAHIRO YAMANAKA ◽  
AKINOBU SHIGA
Keyword(s):  
Interaction Analysis ◽  
Palladium Complexes ◽  
Orbital Interaction ◽  
Frontier Orbital ◽  
System A ◽  
Analysis System

A new orbital interaction analysis system, "LUMMOX", is based on two theories of "Paired Interacting Orbital (PIO)" and "Localized Frontier Orbital (LFO)", which have been developed by Fujimoto et al. LUMMOX can readily estimate the reactivity of an interacting system A–B of various sizes with the same A by comparing with the same number of the interacting orbitals. By applying LUMMOX, we report herein the primary orbital interaction on the phosphine-palladium complexes ( PF 3 Pd , PH 3 Pd , PMe 3 Pd , PPh 3 Pd ) continuously changes from the donative to back-donative interaction.

Total Nitrogen in Fertilizer: Collaborative Study

1978 ◽  
Vol 61 (2) ◽  
pp. 299-306
Author(s):  
Paul R Rexroad ◽  
Gary F Krause
Keyword(s):  
Total Nitrogen ◽  
Collaborative Study ◽  
Oxidation Catalyst ◽  
Official Method ◽  
Probability Level ◽  
Sulfate Sulfur ◽  
Powder Method ◽  
Modified Method ◽  
Accuracy And Precision ◽  
Cent Nitrogen

Abstract A modified comprehensive nitrogen method, using 0.4 g C11SO4 as catalyst, is presented. This method plus a modified Raney powder method (mercury-free) with no metallic oxidation catalyst are compared with the AOAC comprehensive nitrogen method. Results from 19 collaborating laboratories for 11 samples are evaluated. The modified Raney method gave significantly low results on 2 samples: 21-7-14 (nitric phosphates-non-sulfate sulfur) and tryptophan. The results for the average per cent nitrogen for 11 samples from the modified comprehensive nitrogen method were comparable to those from the official method at the 95 % probability level; the overall pooled standard deviations were also similar. In this collaborative study, the modified method (with copper) was equal in accuracy and precision to the official method (with mercury). The modified comprehensive nitrogen method has been adopted as official first action.

scholarly journals Liquid Chromatographic Determination of Methylxanthines and Catechins in Herbal Preparations Containing Guaraná

1998 ◽  
Vol 81 (4) ◽  
pp. 691-701 ◽  
Author(s):  
Marvin Carlson ◽  
Richard D Thompson
Keyword(s):  
Phosphate Buffer ◽  
Chromatographic Determination ◽  
Nutritional Supplement ◽  
The United States ◽  
Precision Data ◽  
Herbal Preparations ◽  
Solid Dosage ◽  
System A ◽  
Relative Standard ◽  
Liquid Chromatographic

Abstract Herbal preparations derived from the dried seeds of guarana (Paullinia cupana) have become a popular nutritional supplement used for stimulatory purposes. Once considered a drug substance in the United States, guaraná currently is classified as a food additive and dietary supplement. The pharmacological activity of guaraná-containing products is primarily due to methylxanthine alkaloids. For guaraná preparations, methylxanthine levels and, more significantly, the presence of several polyphenol compounds (i.e., catechins) provide phytochemical markers of authenticity. Methylxanthines and polyphenols are extracted from sample matrix with a heated phosphate buffer-methanol solution, the cooled extract is filtered, and the extract is injected into the liquid chromatographic (LC) system. A Nova-Pak C18 column eluted with phosphate buffer-methanol mobile phase (pH = 3.50) and monitored at 272 nm gave satisfactory resolution for the methylxanthines theobromine, theophylline, caffeine and the polyphenols (+)-catechin and (−)-epicatechin. Twenty-four products including dried seeds, dried paste, seed powders, tablets, and capsule formulations were assayed and conclusions were drawn about their authenticity. The LC system responded linearly to methylxanthines over the 100-fold range in concentration from 0.043 to 4.30 μg/mL for theobromine and caffeine and from 0.041 to 4.10 μg/mL for theophylline. Precision data for the 3 methylxanthines obtained from 10 different products (n = 5) gave relative standard deviation (RSD) values of 1.18-15.52% within a concentration range of 0.01-52.28 mg/g. Recoveries of methylxanthines from fortified products varied from 87.5 to 120.0%. The response for catechins was linear over a 200-fold range in concentration of 0.05-10.0 μg/mL. Precision data from 5 products (n = 5) gave RSD values of 1.08-5.54% within a concentration range of 0.34-32.65 mg/g. Recoveries from these products ranged from 87.7 to 109.7%. Results and chromatographic profiles for 14 commercial products in solid dosage form indicate that a number of these products may not contain authentic guaraná as an active ingredient or contain less than the declared quantity of guaraná. The proposed procedure also was applied to 2 carbonated soft drinks and a sample of mate.

Development of a Submilli-PIXE Camera

1998 ◽  
Vol 08 (02n03) ◽  
pp. 209-216 ◽  
Author(s):  
S. MATSUYAMA ◽  
K. GOTOH ◽  
K. ISHII ◽  
H. YAMAZAKI ◽  
T. SATOH ◽  
...  
Keyword(s):  
Spatial Distribution ◽  
Spatial Resolution ◽  
Data Acquisition System ◽  
Beam Line ◽  
Beam Position ◽  
Pixe Analysis ◽  
X Ray ◽  
System A ◽  
Line Beam ◽  
Analysis System

We developed a PIXE analysis system which provides spatial distribution images of elements in a region of several cm2 with a spatial resolution of < 0.5 mm. We call this system a submilli-PIXE camera. This system consists of a submilli-beam line, beam scanners and a data acquisition system in which the X-ray energy and the beam position are simultaneously measured. We demonstrate the usefulness of the submilli-PIXE camera by analyzing the surface of a shell and of granite.

The Query Analysis System: A New Tool for Increasing the Effectiveness of Library Utilization by Sociology Students

1978 ◽  
Vol 6 (1) ◽  
pp. 47 ◽  
Author(s):  
Thomas E. Drabek ◽  
Ward Shaw ◽  
Patricia B. Culkin
Keyword(s):  
System A ◽  
Analysis System

A Working Model of a Fully Digital Academic High-Throughput Microscopy Facility

1998 ◽  
Vol 4 (S2) ◽  
pp. 72-73
Author(s):  
M. R. Dickson
Keyword(s):  
Microprobe Analysis ◽  
List Type ◽  
Experimental Science ◽  
Science And Engineering ◽  
Image Capture ◽  
The Past ◽  
System A ◽  
Analysis System ◽  
The University ◽  
Selection Of

The Electron Microscope Unit at the University has a good selection of microscopes: two tungsten SEMs, two FESEMs, a microprobe analysis system, a 125 kY TEM, a 200 kV TEM, an AFM, an FIB miller, a Zeiss Photomicroscope and a Leica Macroscope. We service around 300 clients’ projects a year in every field of experimental science and engineering, logging over 8,000 hrs of beam time annually.But funding constraints have always kept us short staffed and our laboratory has been working towards complete digital image capture for the past ten years to enhance our productivity. The perceived benefits of digitisation for us are:Photographic processing of negatives eliminated.Archiving of (bulky) photographic negatives eliminated.Need for special darkroom & graphics skills eliminatedResponsibility for archiving and indexing images devolved to individual usersResponsibility for image processing devolved to individual users.Rapid turnaround of images.Rapid sharing of results.

An Improved Raney Catalyst Powder Method for Determination of Nitrogen in Fertilizers

1965 ◽  
Vol 48 (6) ◽  
pp. 1111-1115
Author(s):  
W G Burch ◽  
J A Brabson
Keyword(s):  
Sulfuric Acid ◽  
Total Nitrogen ◽  
Organic Nitrogen ◽  
Nitrogen Compounds ◽  
Test Results ◽  
Powder Method ◽  
Catalyst Powder ◽  
Good Agreement

Abstract With a Raney catalyst powder containing 10% Co, 40%; Ni, and 50% Al, nitrates are reduced to ammonia in 8N sulfuric acid in 10 minutes. Neither chlorides nor organic nitrogen compounds interfere with the reduction, and the reduction passed Youden’s ruggedness test. Results of analyses of fertilizers for total nitrogen that included reduction with the powder were in good agreement with those of accepted methods.

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