Quality of adsorption data Sample Clauses

Quality of adsorption data. In order to get reliable experimental results from adsorption data, several conditions should be respected. In the following paragraphs, the experimental results quality and reliability are discussed. The reliability of the VSSA approach first depends on the quality of the adsorption data. As a first step, the reproducibility and repeatability of the surface areas obtained by applying the BET and the t-plot transformations of the nitrogen adsorption isotherms were studied in three laboratories. The repeatability of the BET and the total surface area (St) values are quite satisfactory within each laboratory, while the reproducibility between laboratories strongly depends on the degassing conditions applied to the samples. For a comparable degassing conditions, an acceptable reproducibility is obtained i.e. about 7%. This corresponds to the generally accepted margin of error for adsorption data. For porous, nanostructured or coated nanoparticles, the t-plot transformation should be used because only the external surface of the particle should be considered to calculate the VSSA. The internal porosity or the porosity created by the coating can be determined by analysing the low pressure area of the t-plot (low value of t). This requires to have not only good degassing conditions but also a sufficient number of experimental points in the low pressure region and to use the appropriate standard isotherm. In these conditions, the reliability of the t-plot analysis is very good. To get reliable information on nanomaterials, the quality of adsorption data requires: o a good degassing of the sample, under high vacuum, preferably in the adsorption apparatus for a significant number of hours, at room temperature to avoid modification of the sample o to reach adsorption equilibrium at each experimental point o to have enough number of experimental points in the low pressure region of the isotherm, in order to identify the internal porosity or the porosity generated by the coating o ideally a complete adsorption isotherm or at least a sufficient number of experimental points to cover the relative pressure range from 0 up to 0.65. If these conditions are respected, then the analysis of adsorption isotherms via the BET and the t-plot transformations will give reliable results.
AutoNDA by SimpleDocs
Quality of adsorption data.  The procedure for measuring the surface area by nitrogen adsorption isotherms is according to ISO (2006, 2007 and 2010) and IUPAC (1985). The most critical step in the measurement is the outgassing stage, i.e. to clear the adsorbent surface to any adsorbed molecules before the measurements.  The outgassing process of the solid sample can be performed at room temperature, or at a higher temperature to promote desorption of strongly adsorbed species. The pre-treatment conditions must remain sufficiently mild to avoid any modification of the textural characteristics of the sample but severe enough to obtain a good surface clean-up. It is recommended to perform the pre-treatment in the cell used to carry out the adsorption. Whatever the temperature, the solid must be submitted to a minimum vacuum of 10-2 Nm-2 i.e. 10 mPa during at least one hour. Such conditions are readily achieved with the aid of conventional vacuum equipment, usually a combination of a rotary and diffusion pump. In general, the lower the temperature, the longer the outgassing process should be.  A larger the numbers of experimental points are always recommended to measure during the measurements. For nanomaterials and nanostructured materials, it is recommended to multiply the number of points in the low-pressure region of the isotherm. As a consequence, to get appropriate information on nanomaterials, the quality of adsorption data requires o a good degassing of the sample, under vacuum in the adsorption apparatus, during a few hours, at room temperature to avoid modification of the sample o to reach adsorption equilibrium at each experimental point

Related to Quality of adsorption data

  • Quality of Life Improving the quality of life for Americans and others throughout the world.

  • Quality of Services (a) The Consultant shall be responsible for the professional quality, technical accuracy, and the coordination of all designs, drawings, specifications, and other services furnished pursuant to this Agreement.

  • Technical Feasibility of String While ICANN has encouraged and will continue to encourage universal acceptance of all top-­‐level domain strings across the Internet, certain top-­‐level domain strings may encounter difficulty in acceptance by ISPs and webhosters and/or validation by web applications. Registry Operator shall be responsible for ensuring to its satisfaction the technical feasibility of the TLD string prior to entering into this Agreement.

  • STABILITY OF AGREEMENT Section 1 No amendment, alteration or variation of the terms or provisions of this Agreement shall bind the parties hereto unless made and executed in writing.

  • Quality of Service Contractor shall perform its services with care, skill, and diligence, in accordance with the applicable professional standards currently recognized by such profession, and shall be responsible for the professional quality, technical accuracy, completeness, and coordination of all reports, designs, drawings, plans, information, specifications, and/or other items and services furnished under this Agreement. Contractor shall, without additional compensation, correct or revise any errors or deficiencies immediately upon discovery in its reports, drawings, specifications, designs, and/or other related items or services.

  • QUALITY OF GOODS 5.1 The Supplier warrants that on delivery, and for a period of 12 months from the date of delivery (warranty period), the Goods shall:

  • Quality of Work Consultant agrees that all Services performed under this Agreement will conform to the specifications of the College, be free from errors, and be of professional quality according to applicable industry standards. Upon notice by the College, Consultant will promptly correct any defects without charge to the College unless the request is considered new work by both parties.

  • Equality of Treatment Unless otherwise provided in this Agreement, the persons specified in Article 3, who ordinarily reside in the territory of a Contracting State, shall receive equal treatment with nationals of that Contracting State in the application of the legislation of that Contracting State.

  • Survivability of Orders In the event the term of any order or Professional/Technical Services work order (“Order”) placed under this Contract extends past the termination or expiration of this Contract, the terms and conditions of this Contract shall remain in full force and effect as it applies to such order and will continue in effect for such order until the term of that order expires or the order is cancelled or terminated in accordance with the terms of this Contract.

  • Exclusions and Limitations for Third Party Software SUBJECT TO THE EXCLUSION OF DAMAGES STATED IN SECTION 9.2 AND WITH RESPECT TO THIRD PARTY SOFTWARE, UNDER NO CIRCUMSTANCES AND REGARDLESS OF THE NATURE OF ANY CLAIM SHALL SAP OR ITS LICENSORS’ BE LIABLE FOR AN AMOUNT IN EXCESS OF THE PAID LICENSE FEES FOR THE THIRD PARTY SOFTWARE DIRECTLY CAUSING THE DAMAGES.

Time is Money Join Law Insider Premium to draft better contracts faster.