Image definition evaluation functions for X-ray crystallography a new idea on the phase problem
更新时间:2023-05-30 23:09:01 阅读量: 实用文档 文档下载
- image推荐度:
- 相关推荐
Image definition evaluation functions for X-ray crystallography: A new perspective on the
phase problem
Hui LI*, Meng HE* and Ze ZHANG
Beijing University of Technology, Beijing 100124, People’s Republic of China
CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, National Center for
Nanoscience and Technology, Beijing 100190, People’s Republic of China
Zhejiang University, Hangzhou 310014, People’s Republic of China
Correspondence e-mail: huilicn@ mhe@
In memoriam of Ms. Guang-Lian Tian
05/March/2015
Abstract
The core theme of X-ray crystallography is reconstructing the electron density distribution of crystals under the constraints of observed diffraction data. Nevertheless, the reconstruction of electron density distribution by straightforward Fourier synthesis is usually hindered due to the well-known phase problem and finite resolution of diffraction data. In analogy with optical imaging system, the reconstructed electron density map may be regarded as the image of the real electron density distribution in crystals. Inspired by image definition evaluation functions applied in auto-focusing process, we proposed two evaluation functions for the reconstructed electron density images. One of them is based on atomicity of electron density distribution and properties of Fourier synthesis. Tests were performed on synthetic data of known structures, and it was found that this evaluation function can distinguish the correctly reconstructed electron density image from wrong ones when diffraction data of atomic resolution is available. An algorithm was established based on this evaluation function and applied in reconstructing the electron density image from synthetic data of known structures. The other evaluation function, which is based on the positivity of electron density and constrained entropy maximization, was designed for cases where only diffraction data of rather limited resolution is available. Tests on synthetic data indicate that this evaluation function may identify the correct phase set even for a dataset at the resolution as low as 3.5 Å. Though no algorithm of structure solution has been figured out based on the latter function, the results presented here provide a new perspective on the phase problem.
Keywords: phase problem; X-ray crystallography; image definition function; charge density map; algorithms
正在阅读:
Image definition evaluation functions for X-ray crystallography a new idea on the phase problem05-30
客户分级经营管理策略06-07
节约粮食从我做起作文600字06-19
牧师在T2之前必须收集的治疗装 - 图文11-30
研修任务初中语文《山的那边》教学设计03-18
戴云山隧道专项风险评估 - 图文04-21
七选五阅读03-06
2011年温州中学自主招生物理试卷07-21
五一问候短信02-18
- 1oracle functions 函数大全
- 2Computation of Complex Scorer Functions
- 3Though the definition of the public school is vague
- 4Acronis True Image 使用教程
- 5National Identity and the Idea of European Unity
- 6相位误差phase error question
- 7IMAGE J灰度分析
- 8Problem-based Learning in Mathematics
- 9Problem-based Learning in Mathematics
- 10normalized cuts and image segmentation翻译
- 教学能力大赛决赛获奖-教学实施报告-(完整图文版)
- 互联网+数据中心行业分析报告
- 2017上海杨浦区高三一模数学试题及答案
- 招商部差旅接待管理制度(4-25)
- 学生游玩安全注意事项
- 学生信息管理系统(文档模板供参考)
- 叉车门架有限元分析及系统设计
- 2014帮助残疾人志愿者服务情况记录
- 叶绿体中色素的提取和分离实验
- 中国食物成分表2020年最新权威完整改进版
- 推动国土资源领域生态文明建设
- 给水管道冲洗和消毒记录
- 计算机软件专业自我评价
- 高中数学必修1-5知识点归纳
- 2018-2022年中国第五代移动通信技术(5G)产业深度分析及发展前景研究报告发展趋势(目录)
- 生产车间巡查制度
- 2018版中国光热发电行业深度研究报告目录
- (通用)2019年中考数学总复习 第一章 第四节 数的开方与二次根式课件
- 2017_2018学年高中语文第二单元第4课说数课件粤教版
- 上市新药Lumateperone(卢美哌隆)合成检索总结报告
- crystallography
- definition
- evaluation
- functions
- problem
- Image
- phase
- idea
- ray
- new
- 全景图像拼接算法2_1
- 基于GIS的汉江中下游农业面源氮磷负荷研究
- 正心修身 以上率下
- 整理小学第十一届校园文化艺术节活动方案
- 防汛工作传达汇报情况
- 由两起化工管线事故引起的思考
- 警惕无形杀手关于涂改液的危害和建议
- 《石油建设安装工程预算定额(2013版)》
- 生物化学复习重点
- 男人总是为这五种女人倾倒_追女孩
- 重庆南岸区语文一年级上册入学试卷及答案分析
- 第三章 第一节 模板工程 爬升模板施工
- 廉颇蔺相如列传教案(老师)
- 桂林米粉卤水配方
- 深圳市房屋租赁合同示范文本
- 有效课堂教学点滴谈论文
- 小学一年级书法教案 (1)
- 2016年外交学院国际政治专业考研权威辅导课程学长笔记联系方式-育明教育
- 一个财务总监的避税之路:3分钟节税33亿
- 对我国开征环境保护税的研究