A PHP Error was encountered

Severity: Warning

Message: file_get_contents(https://...@pubfacts.com&api_key=b8daa3ad693db53b1410957c26c9a51b4908&a=1): Failed to open stream: HTTP request failed! HTTP/1.1 429 Too Many Requests

Filename: helpers/my_audit_helper.php

Line Number: 176

Backtrace:

File: /var/www/html/application/helpers/my_audit_helper.php
Line: 176
Function: file_get_contents

File: /var/www/html/application/helpers/my_audit_helper.php
Line: 250
Function: simplexml_load_file_from_url

File: /var/www/html/application/helpers/my_audit_helper.php
Line: 3122
Function: getPubMedXML

File: /var/www/html/application/controllers/Detail.php
Line: 575
Function: pubMedSearch_Global

File: /var/www/html/application/controllers/Detail.php
Line: 489
Function: pubMedGetRelatedKeyword

File: /var/www/html/index.php
Line: 316
Function: require_once

Theory of electron-optical achromats and apochromats. | LitMetric

Theory of electron-optical achromats and apochromats.

Ultramicroscopy

Argonne National Laboratory, Materials Science Division, Argonne, IL 60439, USA.

Published: December 2002

A detailed theoretical formulation of the primary and secondary chromatic aberrations of electron-optical systems with a straight optic axis is outlined. To simplify the mathematical expenditure only systems composed of magnetic round lenses and magnetic and electrostatic quadrupoles are taken into account. By appropriately arranging these elements, it is possible to construct feasible electron-optical analogues of light-optical achromats and apochromats.

Download full-text PDF

Source
http://dx.doi.org/10.1016/s0304-3991(02)00285-1DOI Listing

Publication Analysis

Top Keywords

achromats apochromats
8
theory electron-optical
4
electron-optical achromats
4
apochromats detailed
4
detailed theoretical
4
theoretical formulation
4
formulation primary
4
primary secondary
4
secondary chromatic
4
chromatic aberrations
4

Similar Publications

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!