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完整和非完整固体的电子结构

物理学进展 1981年第2期 195-279页

作者： a.j.freeman Department of Physics and Astronomy Northwestern University Evanston Illinios 60201 USA

在过去十年中,单电子能带理论取得了重大的进展。现在,已不仅可以将能带结构,并且可以将用能量本征函数计算的各种物理的期望值,与精密的实验测量相比较。意图为基态的单粒子能带描述准备严格基础的由Hohenberg,Kohn和Sham创始的局域密... 详细信息

在过去十年中,单电子能带理论取得了重大的进展。现在,已不仅可以将能带结构,并且可以将用能量本征函数计算的各种物理的期望值,与精密的实验测量相比较。意图为基态的单粒子能带描述准备严格基础的由Hohenberg,Kohn和Sham创始的局域密度泛函理论,也提供了从第一性原理出发的准确而有用的计算方法。本文评述局域密度泛函(LDF)理论—能带方法的新近进展。我们首先对于理论的背景作一般性的介绍,然后通过对于各种物理系统的应用的讨论,让读者了解,它们所取得的成就。

关键词：电子结构密度泛函自洽计算电荷密度波能带结构电子能态非完整

C15化合物ZrZn2和ZrV2的磁性和超导性的自洽电子结构研究

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中国科学:数学 1987年第3期 270-279页

作者：黄美纯,H.j.F.jansen,a.j.freeman 厦门大学物理系美国西北大学物理系洛沙拉莫斯国家实验所材料科学中心美国西北大学物理系洛沙拉莫斯国家实验所材料科学中心

本文介绍了新发展的体能带全电子完整势线性缀加平面波（FLAPW）方法,在计算立方Laves相C15化合物ZrZn2和ZrV2电子结构的首次应用.这两种材料的磁性和超导性,己用能带结构的结果进行了计算和讨论.计算分两种情况:（1）扭曲Muffin-tin（M... 详细信息

本文介绍了新发展的体能带全电子完整势线性缀加平面波（FLAPW）方法,在计算立方Laves相C15化合物ZrZn2和ZrV2电子结构的首次应用.这两种材料的磁性和超导性,己用能带结构的结果进行了计算和讨论.计算分两种情况:（1）扭曲Muffin-tin（MT）势的自洽计算,（2）应用二次变分的完整势处理.上述计算都在达到自洽后将自旋轨道耦合效应包括进去.在MT球内的非球对称项对本征值的影响约为1mRy量级.但是,由于在Fermi能级附近存在着平坦的能带,它可能对EF处的态密度产生值得注意的影响.分波态密度的仔细分析表明:ZrZn2和ZrV2之间最主要的差别是原子Zr和V产生的d带的位置不同. 本文通过计算广义Stoner因子,研究了这些材料的磁性.结果发现,ZrZn2存在着磁反常而ZrV2是非磁性的.这一结果同实验观察一致.理论预言ZrV2的超导转变温度Tc～15K,而ZrZn2约为4K.同以前的各种计算比较,本文结果有大幅度的改进.

关键词：电子结构超导性导电性态密度 ZrZn2 C15 自洽布里渊区化合物电子能态能带结构磁性

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堪为物理学第三分支的计算物理

物理学进展 1984年第1期 1-11页

作者： a.j.freeman Department of Physics and Astronomy Northwestern University Evanston Illinois 60201 U.S.A.

本文是作者1982年在中国访问时所作的讲演,论述物理学各领域的前沿工作,用许多事例说明计算物理对推动物理理论的重大意义。文中还指出计算物理在其性质、方法及需要等方面不同于和独立于解析的理论物理和实验物理,而成为物理学的第三... 详细信息

本文是作者1982年在中国访问时所作的讲演,论述物理学各领域的前沿工作,用许多事例说明计算物理对推动物理理论的重大意义。文中还指出计算物理在其性质、方法及需要等方面不同于和独立于解析的理论物理和实验物理,而成为物理学的第三分支。

关键词：计算物理物理学分支

Pancreatic endocrine and exocrine changes in celiac disease

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World journal of Gastroenterology 2007年第47期13卷 6344-6346页

作者： Hugh j freeman Department of Medicine (Gastroenterology) University of British ColumbiaVancouverBCCanada

Although there is a great deal of information on celiac disease and associated involvement of other non-intestinal sites,data on concomitant changes in the structure and function of the pancreas is limited. The present review critically examines pancreatic endocrine changes that have been well documented in the literature,including insulin-dependent diabetes mellitus. Pancreatic exocrine alterations may also occur,and if severe,marked malnutrition with pancreatic failure and ductal calcification have been observed. Finally,other pancreatic disorders have been recorded with celiac disease.

关键词： Celiac disease Gluten-sensitive enteropathy Diabetes mellitus Chronic pancreatitis Pancreatic function

Endoscopic excision of a prolapsing malignant polyp which caused intermittent gastric outlet obstruction

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World journal of Gastroenterology 2005年第33期11卷 5245-5247页

作者： Hugh j freeman Department of Medicine (Gastroenterology) University of British Columbia Vancouver BC V6T 1W5 Canada Correspondence to:Dr.Hugh J FreemanGastroenterologyUBC Hospital2211 Wesbrook MallVancouverBCV6T 1W5

A 69-year-old male with chronic lymphocytic leukemia presented with iron deficiency anemia and post-prandial abdominal fullness. Endoscopy showed a large polyp on a stalk, protruding through the pylorus into the duodenum causing intermittent gastric outlet obstruction. While prolapsing gastric antral polyps are usually benign and hyperplastic, inflammatory or regenerative in type, excisional snare polypectomy here led to complete resolution of his symptoms, but showed a malignant polyp.

关键词： Gastric adenoma Gastric carcinoma Endoscopic polypectomy Neoplastic gastric polyps

The spirit of Henry Norman Bethune and gastroenterology

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World journal of Gastroenterology 2008年第2期14卷 174-179页

作者： Hugh j freeman Department of Medicine University of British Columbia Vancouver BC Canada

Henry Norman Bethune was a physician and surgeon from Canada. He had a highly impressive medical career in Montreal but did his most important work in China where he cared for soldiers on the battlefield. He died in 1939 and was recognized as a hero, but only much later received recognition in Canada. He was a skilled doctor, both as a physician and as a surgeon. However, he was much more and will serve as an inspiration for this series. He was an innovator, an idealist and a perfectionist. It is hoped that this series will gather expert commentaries on a range of issues critical to the subspecialty from fundamental science to clinical care so that future directions can be defined.

关键词： Bethune Gastroenterology China Canada Battlefield surgery

Segmental colitis associated diverticulosis syndrome

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World journal of Gastroenterology 2016年第36期22卷 8067-8069页

作者： Hugh j freeman Department of Medicine(Gastroenterology) University of British Columbia

Segmental colitis associated diverticulosis(SCAD) has become increasingly appreciated as a form of inflammatory disease of the colon. Several features suggest that SCAD is a distinct disorder. SCAD tends to develop almost exclusively in older adults, predominately, but not exclusively, males. The inflammatory process occurs mainly in the sigmoid colon, and usually remains localized to this region of the colon alone. SCAD most often presents with rectal bleeding and subsequent endoscopic visualization reveals a well localized process with non-specific histopathologic inflammatory changes. Granulomas are not seen, and if present, may be helpful in definition of other disorders such as Crohn's disease of the colon, an entity often confused with SCAD. Bacteriologic and parasitic studies for an infectious agent are negative. Normal rectal mucosa(i.e., "rectal sparing") is present and can be confirmed with normal rectal biopsies. SCAD often resolves spontaneously without treatment, or completely after a limited course of therapy with only a 5-aminosalicylate. Recurrent episodes may occur, but most often, patients with this disorder have an entirely self-limited clinical course. Occasionally, treatment with other agents, including corticosteroids, or surgical resection has been required.

关键词： Segmental colitis associated Diverticulosis syndrome Ulcerative colitis Diverticulitis Segmental colitis Diverticulosis Inflammatory bowel disease

Duplicated appendix complicated by appendiceal cancer

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World journal of Gastroenterology 2011年第1期17卷 135-136页

作者： Hugh j freeman Department of Medicine(Gastroenterology) University of British Columbia HospitalVancouverBCV6T 1W5Canada

A 37-year old male presented with an acute abdomen suggestive of an appendiceal *** laparotomy showed a duplicated appendix with one of the lumens involved with appendicitis and a focal periappendicular abscess while the other lumen had a localized appendiceal *** of congenital intestinal duplications in adults is important to avoid serious clinical consequences.

关键词： Duplicated appendix Bifid appendix Appendiceal cancer Congenital duplication.

A chaotic neural network mimicking an olfactory system and its application on image recognition

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journal of Bionic Engineering 2004年第3期1卷 191-198页

作者： Walter j. freeman Department of Molecular & Cell Biology UCB LSA 142 Berkeley CA 94720-3200 USA

Based on the research of a biological olfactory system, a novel chaotic neural network model - K set model has been es- tablished. This chaotic neural network not only simulates the real brain activity of an olfactory system, but also presents a novel chaotic concept for signal processing and pattern recognition. The characteristics of the K set models are investigated and show that a KIII model can be used for image pattern classification.

关键词： olfactory system pattern recognition neural networks image classification

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