A New Approach to the Raney Catalyst Powder Method for Total Nitrogen in Fertilizers

1969 ◽  
Vol 52 (1) ◽  
pp. 23-30 ◽  
Author(s):  
J A Brabson ◽  
T C Woodis
Keyword(s):  
Sulfuric Acid ◽  
Refractory Compound ◽  
Potassium Sulfate ◽  
Dilute Solution ◽  
Commercial Alloy ◽  
New Approach ◽  
Powder Method ◽  
Catalyst Powder ◽  
Time Required

Abstract Further study of the Raney catalyst powder method for the determination of nitrogen in fertilizers established conditions in which the commercial alloy containing 50% Ni and 50% Al was a more efficient reductant for nitrates than an experimental alloy that contained 10% Co. Errors in measurement were decreased, accuracy was increased, and time was saved by adding all the sulfuric acid and part of the potassium sulfate as a single dilute solution and heating the mixture immediately to promote the reduction. Changes in the amounts of reagents, including use of the contents of a Kcl-Pak without the polyethylene envelope, resulted in smoother and more effective Kjeldahl digestions. The method is “rugged” and is equally applicable to the refractory compound nicotinic acid, mixtures of nitrates and organic materials, and the simplest inorganic fertilizers. The time required for an analysis can be further shortened by using “Autopettes” for dispensing the standard acid and a “Titralyzer” for back titrations.

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.

scholarly journals The determination of organic matter in air

1887 ◽  
Vol 41 (246-250) ◽  
pp. 238-247 ◽  
Keyword(s):  
Organic Matter ◽  
Oxalic Acid ◽  
Potassium Permanganate ◽  
Water Analysis ◽  
Distilled Water ◽  
Dilute Solution ◽  
Single Determination ◽  
Time Required

The Only methods hitherto proposed for determining the amount of organic matter in air are the two devised by the late Dr. Angus Smith (“Air and Rain”). According to the first of these methods, a defi­nite quantity of the air to be examined is slowly bubbled through a dilute solution of potassium permanganate of known strength until it is fully or considerably bleached,' and in the latter ease the amount of undecomposed permanganate determined by oxalic acid. In the second method a known volume of air is bubbled through distilled water, and the latter examined for free and albuminoid ammonia by Wanklyn and Chapman’s process for water analysis. These methods are open to one or more of the following objec­tions :— 1. The time required for a single determination is very considerable , and recessarily varies with the amount of organic matter present.

An Unforeseen Problem in the Use of Kel-Paks

1968 ◽  
Vol 51 (6) ◽  
pp. 1290-1295
Author(s):  
T C Woodis ◽  
J A Brabson ◽  
W G Burch
Keyword(s):  
Salicylic Acid ◽  
Nicotinic Acid ◽  
Organic Compounds ◽  
Total Nitrogen ◽  
Ammoniacal Nitrogen ◽  
Powder Method ◽  
Catalyst Powder ◽  
Possible Cause ◽  
Digestion Step

Abstract In Kjeldahl methods for the determination of nitrogen in fertilizers, the digestion temperature must be above 370°C to mineralize the nitrogen in refractory organic compounds such as nicotinic acid. In total nitrogen determinations by the Raney catalyst powder method, temperatures during the digestion step were investigated as a possible cause of occasional low results. Decomposition of the polyethylene envelopes of Kel-Paks in the presence of salts of metallic reductants caused rapid fluctuations and excessive rise in temperature with consequent loss of ammoniacal nitrogen. Complete Kel-Paks can be used without difficulty in methods such as 2.044 (for nitrate-free samples) or 2.045 (salicylic acid) that do not use metallic reductants, but only the contents of the Kel-Paks without the envelopes should be used when Raney catalyst or chromium powders have been used to reduce nitrates.

Determination of Total Nitrogen in Fertilizers

1965 ◽  
Vol 48 (2) ◽  
pp. 401-406
Author(s):  
H A Davis ◽  
W E Urban
Keyword(s):  
Nickel Catalyst ◽  
Raney Nickel ◽  
Total Nitrogen ◽  
Official Method ◽  
Chromium Powder ◽  
Powder Method ◽  
Raney Nickel Catalyst ◽  
Catalyst Powder ◽  
Iron Chromium

Abstract Five methods, AOAC 2.037, 2.039, modified reduced iron, chromium powder, and Raney nickel catalyst powder for the determination of total nitrogen in fertilizers, were submitted to collaborators for study. Twelve laboratories participated and completed the work. No one method was “best.” The modified reduced iron, chromium powder, and Raney nickel catalyst powder methods gave essentially equal results, but the chromium powder method is favored for case of operation and time required. However, if considerable organic matter and nitrate are present in a sample, satisfactory results may not be obtained. The analyst should select the official method best suited to the makeup of the sample. It is recommended that the chromium powder method he adopted as official, first action, and that study be continued with the modified reduced iron and Raney nickel catalyst methods, including helpful proposals in developing a method that may be applicable to all fertilizers.

How Rugged Are Our Nitrogen Methods?

1965 ◽  
Vol 48 (3) ◽  
pp. 501-507
Author(s):  
W G Burgh ◽  
J A Brabson
Keyword(s):  
Salicylic Acid ◽  
Standard Deviation ◽  
Total Nitrogen ◽  
Reduction Method ◽  
Official Method ◽  
Powder Method ◽  
Catalyst Powder ◽  
Time Of Reaction

Abstract Youden’s ruggedness test was made of two official methods and four more recent methods for the determination of total nitrogen in fertilizers containing nitrates. Among the variables tested were amounts of nitrogen and reductant, effect of chloride, and time of reaction of reductant. Official method 2.039 (reduced-iron) failed the test. In order of increasing standard deviation, the five methods that passed the test were the chromous reduction method, Raney-catalyst-powder method, official method 2.037 (salicylic acid), improved reduced-iron method, and the chromiumpowder method.

Study of sugars with cysteine – sulfuric acid reagents

1969 ◽  
Vol 47 (2) ◽  
pp. 203-206 ◽  
Author(s):  
R. J. Thibert ◽  
A. Mazzuchin
Keyword(s):  
Sulfuric Acid ◽  
Optimum Concentration ◽  
Complete Analysis ◽  
Cysteine Hydrochloride ◽  
Acid Reagent ◽  
Time Required ◽  
Optimum Concentration Range

A modified procedure for the use of the cysteine – sulfuric acid reagent for the determination of monosaccharide has been devised. The procedure utilizes a 9-ml volume of H2O:H2SO4 at a ratio of 1:7 which results in a rapid nonspecific method for the determination of pentoses, hexoses, and hexuronic acids in simple solutions. α-Substituted cysteines are compared to cysteine hydrochloride as color reagents. The accuracy of the modified procedure is about ± 2% in the optimum concentration range. The time required for a complete analysis is about 1 h for pentoses and hexuronic acids and 30 min for hexoses.

The Dudley Lee Case: A new approach to factual causation and its implications for transformative jurisprudence

2017 ◽  
Vol 30 (1) ◽  
pp. 273-289
Author(s):  
Anmari Meerkotter
Keyword(s):  
Case Note ◽  
Constitutional Court ◽  
Recent Contribution ◽  
New Approach ◽  
State Accountability ◽  
The Law ◽  
Transformative Impact ◽  
Constitutional Jurisprudence ◽  
Law Of Delict

The Constitutional Court (CC) judgment of Lee v Minister of Correction Services 2013 2SA 144 (CC) is a recent contribution to transformative constitutional jurisprudence in the field of the law of delict. This matter turned on the issue of factual causation in the context of wrongful and negligent systemic omissions by the state. In this case note, I explore the law relating to this element of delictual liability with specific regard to the traditional test for factual causation – the conditio sine qua non (‘but-for’) test. In particular, I note the problems occasioned by formalistic adherence to this test in the context of systemic state omissions as evidenced by the SCA judgment in the same matter. I also consider the manner in which English courts have addressed this problem. Thereafter, I analyse the CC’s broader approach to the determination of factual causation as one based on common sense and justice. I argue that this approach endorses a break from a formalistic application of the test and constitutes a step towards an approach which resonates with the foundational constitutional values of freedom, dignity and equality. Furthermore, it presents an appropriate solution to the problems associated with factual causation where systemic omissions are concerned. I then consider the transformative impact of the Lee judgment. In particular, I argue that the broader enquiry favoured by the CC facilitates the realisation of constitutionally guaranteed state accountability, and amounts to an extension of the existing norm of accountability jurisprudence. Hence, I contend that the judgment presents a further effort by the Constitutional Court to effect wholesale the constitutionalisation of the law of delict, as well as a vindicatory tool to be used by litigants who have been adversely affected by systemic state omissions.

Automatic Determination of Optimal FIB Operations for Improved Circuit Probing and Fast Reconfiguration

2000 ◽  
Author(s):  
Romain Desplats ◽  
Timothee Dargnies ◽  
Jean-Christophe Courrege ◽  
Philippe Perdu ◽  
Jean-Louis Noullet
Keyword(s):  
Integrated Circuit ◽  
Focused Ion Beam ◽  
Ion Beam ◽  
Semiconductor Devices ◽  
Front Side ◽  
Automatic Determination ◽  
Metal Line ◽  
New Approach ◽  
Metal Layers

Abstract Focused Ion Beam (FIB) tools are widely used for Integrated Circuit (IC) debug and repair. With the increasing density of recent semiconductor devices, FIB operations are increasingly challenged, requiring access through 4 or more metal layers to reach a metal line of interest. In some cases, accessibility from the front side, through these metal layers, is so limited that backside FIB operations appear to be the most appropriate approach. The questions to be resolved before starting frontside or backside FIB operations on a device are: 1. Is it do-able, are the metal lines accessible? 2. What is the optimal positioning (e.g. accessing a metal 2 line is much faster and easier than digging down to a metal 6 line)? (for the backside) 3. What risk, time and cost are involved in FIB operations? In this paper, we will present a new approach, which allows the FIB user or designer to calculate the optimal FIB operation for debug and IC repair. It automatically selects the fastest and easiest milling and deposition FIB operations.

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