Author: Farlow Reference Library and Herbarium
Publisher: MacMillan Publishing Company
ISBN:
Category : Reference
Languages : en
Pages : 634
Book Description
Entomology Current Literature
Author:
Publisher:
ISBN:
Category : Entomology
Languages : en
Pages : 382
Book Description
Publisher:
ISBN:
Category : Entomology
Languages : en
Pages : 382
Book Description
Catalog of the Farlow Reference Library of Cryptogamic Botany, Harvard University
Author: Farlow Reference Library and Herbarium
Publisher: MacMillan Publishing Company
ISBN:
Category : Reference
Languages : en
Pages : 634
Book Description
Publisher: MacMillan Publishing Company
ISBN:
Category : Reference
Languages : en
Pages : 634
Book Description
Modern Methods of Plant Analysis / Moderne Methoden der Pflanzenanalyse
Author: K. Biemann
Publisher: Springer Science & Business Media
ISBN: 3642459935
Category : Science
Languages : en
Pages : 563
Book Description
123 phase and hence have no direct bearing on the retention time of solutes. However in gas-solid chromatography, a considerable quantity of the mobile phase may be adsorbed on the surface of the stationary adsorbent which diminishes the column's effective length and ability to retain solutes. In this respect helium has been found to be preferable to most other gases (GREENE and Roy, 1957) because it is adsorbed to the least extent. 3. Packed columns offer a considerable resistance to flow, which may create a pressure differential between inlet and outlet of sufficient magnitude to cause an unfavorable flow rate through a significant length of the column. A reduced inlet/outlet pressure ratio can be obtained by using light molecular weight gases toward which the column packing shows the greatest permeability. The flow rate of the mobile phase is normally adjusted by altering the column inlet pressure, for which purpose commercial pressure regulators of sufficient accuracy are available. Quantitative measurements of the flow rate can be made by a number of methods, including rotameters, orifice meters, soapfilm flow meters and displacement of water. The former two methods are the most con venient but the least accurate; moreover they create a back pressure and are temperature dependent whereas although the moving soap bubble is cumbersome to employ and unusable for continuous readings, it is preferred when the highest accuracy is required.
Publisher: Springer Science & Business Media
ISBN: 3642459935
Category : Science
Languages : en
Pages : 563
Book Description
123 phase and hence have no direct bearing on the retention time of solutes. However in gas-solid chromatography, a considerable quantity of the mobile phase may be adsorbed on the surface of the stationary adsorbent which diminishes the column's effective length and ability to retain solutes. In this respect helium has been found to be preferable to most other gases (GREENE and Roy, 1957) because it is adsorbed to the least extent. 3. Packed columns offer a considerable resistance to flow, which may create a pressure differential between inlet and outlet of sufficient magnitude to cause an unfavorable flow rate through a significant length of the column. A reduced inlet/outlet pressure ratio can be obtained by using light molecular weight gases toward which the column packing shows the greatest permeability. The flow rate of the mobile phase is normally adjusted by altering the column inlet pressure, for which purpose commercial pressure regulators of sufficient accuracy are available. Quantitative measurements of the flow rate can be made by a number of methods, including rotameters, orifice meters, soapfilm flow meters and displacement of water. The former two methods are the most con venient but the least accurate; moreover they create a back pressure and are temperature dependent whereas although the moving soap bubble is cumbersome to employ and unusable for continuous readings, it is preferred when the highest accuracy is required.
The Southwestern Pinyon-juniper Ecosystem
Author: Earl F. Aldon
Publisher:
ISBN:
Category : Forest ecology
Languages : en
Pages : 750
Book Description
Publisher:
ISBN:
Category : Forest ecology
Languages : en
Pages : 750
Book Description
National Union Catalog
Author:
Publisher:
ISBN:
Category : Union catalogs
Languages : en
Pages : 1032
Book Description
Publisher:
ISBN:
Category : Union catalogs
Languages : en
Pages : 1032
Book Description
National Library of Medicine Current Catalog
Author: National Library of Medicine (U.S.)
Publisher:
ISBN:
Category : Medicine
Languages : en
Pages : 1380
Book Description
Publisher:
ISBN:
Category : Medicine
Languages : en
Pages : 1380
Book Description
Publications of the Children's Bureau
Author: United States. Children's Bureau
Publisher:
ISBN:
Category : Child welfare
Languages : en
Pages : 684
Book Description
Publisher:
ISBN:
Category : Child welfare
Languages : en
Pages : 684
Book Description
Bureau Publication ...
Author:
Publisher:
ISBN:
Category : Child welfare
Languages : en
Pages : 752
Book Description
Publisher:
ISBN:
Category : Child welfare
Languages : en
Pages : 752
Book Description
National Library of Medicine Catalog
Author: National Library of Medicine (U.S.)
Publisher:
ISBN:
Category : Medicine
Languages : en
Pages : 892
Book Description
Publisher:
ISBN:
Category : Medicine
Languages : en
Pages : 892
Book Description
Norwegian Laws Concerning Illegitimate Children
Author: Norway
Publisher:
ISBN:
Category : Child welfare
Languages : en
Pages : 1304
Book Description
Publisher:
ISBN:
Category : Child welfare
Languages : en
Pages : 1304
Book Description