Preparation and use

Bonnemann H ef a/1996 Nanoscale colloidal metals and alloys stabilized by solvents and surfactants preparation and use as catalyst precursors J. Organometaii. Chem. 520 143... 

Pure Ether. Pure ether (entirely free in particular from water) is frequently required in the laboratory, and especially for the preparation and use of Grignard reagents. It is best prepared in quantity for classes by adding an ample quantity of granular calcium chloride to a Winchester bottle of technical ether, and allowing the mixture to stand for at least 24 hours, preferably with occasional shaking. The greater part of the water and... 

Carbon monoxide is very poisonous all operations involving its preparation and use must be carried out in an efficient fume cupboard. 

It is preferable to use Tollen s ammoniacal silver nitrate reagent, which is prepared as follows Dissolve 3 g. of silver nitrate in 30 ml. of water (solution A) and 3 g. of sodium hydroxide in 30 ml. of water (solution B). When the reagent is requir, mix equal volumes (say, 1 ml.) of solutions A and JB in a clean test-tube, and add dilute ammonia solution drop by drop until the silver oxide is just dissolved. Great care must be taken in the preparation and use of this reagent, which must not be heated. Only a small volume should be prepared just before use, any residue washed down the sink with a large quantity of water, and the test-tubes rinsed with dilute nitric acid. 

Directions are provided for preparing and using a simple coring device using PVC pipe. This experiment also details a procedure for determining the weight percent of organic material in sediments as a function of depth. 

Sittampalam and Wilson described the preparation and use of an amperometric sensor for glucose. " The sensor is calibrated by measuring the steady-state current when it is immersed in standard solutions of glucose. A typical set of calibration data is shown in the following table. 

Fluorosulfuric acid can be very corrosive. A study of the corrosive properties of fluorosulfuric acid during preparation and use showed carbon steel to be acceptable up to 40°C, stainless steel up to 80°C, and aluminum alloys up to 130°C (52). 

The successful employment of any insecticide depends on its proper formulation into a preparation that can be appHed for insect control with safety to the apphcator, animals, and plants. Insecticides are commonly formulated as dusts, water dispersions, emulsions, and solutions. The preparation and use of such formulations involves accessory agents such as dust carriers, solvents, emulsifiers, wetting and dispersing agents, stickers, and deodorants or masking agents (1). 

Great care must be exercised ia the preparation and use of Ziegler-Natta catalysts. They are easily poisoned by moisture, among other things. They are pyrophoric and are used ia conjunction with large amounts of flammable monomer and solvent, and so can present a significant safety hazard. 

The preparation and use of histograms is the fourth TOQ (46). These charts, such as that shown in Figure 5, illustrate the variabiUty of data as a... 

Highway Construction. The preparation and use of sulfur—asphalt (SA) paving materials have been reviewed (45,46). In the 1930s, asphalt (qv) was easily available and priced lower than sulfur. As of the 1990s, this is no longer the case. There are four different types of sulfur paving materials. 

As a beverage ethanol had been prepared and used long ago by the Egyptian pharaohs (2,3). Some iadication of the antiquity of the knowledge of ethyl alcohol is the fact that Noah is beheved to have built a vineyard ia which he grew grapes that he fermented iato a type of alcohoHc beverage (4). 

Several methoxy-substituted benzyl ethers have been prepared and used as protective groups. Their utility lies in the fact that they are more readily cleaved oxidatively than the unsubStituted benzyl ethers. The table below gives the relative rates of cleavage with dichlorodicyanoquinone (DDQ). ... 

The related 2-/-butyl derivative has also been prepared and used to advantage as a temporary protective group for the stereogenic center of amino acids during alkylations. ... 

Unlike perfluoroaliphatic organometallies, perfluoroolefinic and perfluoro-acetylemc Grignard reagents have a greater thermal stability and can be prepared and used as intermediates at temperatures around 0 C [40]... 

Reactions offluorinated dipoles. In recent years, much effort has been devoted to the preparation of tnfluoromethyl-substituted 1,3-dipoles with the goal of using them to introduce trifluoromethyl groups into five-membered nng heterocycles Fluorinated diazoalkanes were the first such 1,3-dipoles to be prepared and used in synthesis A number of reports of cycloadditions of mono- and bis(tnfluo-romethyl)diazomethane appeared prior to 1972 [9] Other types of fluonne-substi-tuted 1,3-dipoles were virtually unknown until only recently However, largely because of the efforts of Tanaka s group, a broad knowledge of the chemistry of tnfluoromethyl-substituted nitrile oxides, nitnle imines, nitnle ylides, and nitrones has been accumulated recently... 

Cross-linked polyacrylamides attached with morpholine pendent at some repeating unit of the backbone chains have been prepared and used for the separation of discrete chemical compounds by gel-permeation chromatography (83). 

When the Ac group is removed (20% piperidine/DMF or 5% hydrazine/DMF), it becomes the Hmb group that is used to improve solubility and prevent aspar-tamide formation and is readily cleaved with TFA. The related 2-Fmoc-4-methoxybenzyl group has also been prepared and used in peptide synthesis. ... 

The preparation and use of LiEt3BT and LiAlT4 at maximum specific activity (57.5 Cimmol" ) has also been described. ... 

This reaction is catalysed by traces of heavy metal ions such as Cu and the purpose of the gelatin is to suppress reaction (5) by sequestering the metal ions it is probable that gelatin also assists the hydrazine-forming reactions between ammonia and chloramine in a way that is not fully understood. The industrial preparation and uses of N2H4 are summarized in the Panel. 

Because of the great importance of phosphorus and its compounds in the chemical industry, several books and reviews on their preparation and uses are available.Some of these applications reflect the fact that P is a vital element for the growth and development of all plants and animals and is therefore an important constituent in many fertilizers. Phosphorus compounds are involved in energy transfer... 

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