检索结果-内蒙古大学图书馆

Bifunctional metamaterials with simultaneous and independent manipulation of thermal and electric fields

OPTICS EXPRESS 2016年第20期24卷 23072-23080页

作者： Lan, chuwen Bi, Ke Fu, Xiaojian li, Bo Zhou, Ji Tsinghua Univ Shenzhen Grad Sch Adv Mat Inst Shenzhen Peoples R China Tsinghua Univ Sch Mat Sci & Engn State Key Lab New Ceram & Fine Proc Beijing 100084 Peoples R China Beijing Univ Posts & Telecommun State Key Lab Informat Photon & Opt Commun Beijing 100876 Peoples R China Beijing Univ Posts & Telecommun Sch Sci Beijing 100876 Peoples R China Southeast Univ Sch Informat Sci & Engn State Key Lab Millimeter Waves Nanjing 210096 Jiangsu Peoples R China

Metamaterials offer a powerful way to manipulate a variety of physical fields ranging from wave fields (electromagnetic field, acoustic field, elastic wave, etc.), static fields (static magnetic field, static electric field) to diffusive fields (thermal field, diffusive mass). However, the relevant reports and studies are usually limited to a single physical field or functionality. In this study, we proposed and experimentally demonstrated a bifunctional metamaterial which could manipulate thermal and electric fields simultaneously and independently. Specifically, a composite with independently controllable thermal and electric conductivity was introduced, on the basis of which a bifunctional device capable of shielding thermal flux and concentrating electric current simultaneously was designed, fabricated and characterized. This work provides an encouraging example of metamaterials transcending their natural limitations, which offers a promising future in building a broad platform for manipulation of multi-physics field. (C) 2016 Optical Society of America

关键词： Electric fields Invisibility cloaks Magnetic fields Material properties Metamaterials Phase space analysis methods

来源：评论

学校读者我要写书评

暂无评论

Isolation and Identification of Serotype O101 Bovine Pathogenic Escherichia coli with Multidrug Resistance

引用

Animal Husbandry and Feed Science 2017年第5期9卷 303-305页

作者： li Shuguang liu Xiaoyun Wang Yumao li Feng lin chuwen Shen Zhiqiang li Jinlin Binzhou Academy of Animal Science&Veterinary Medicine Binzhou 256600China Shandong Lvdu Biotechnology Co. Ltd.Binzhou 256600China Zouping Animal Husbandry and Veterinary Bureau Binzhou 256600China

[Objective]The paper was to isolate and identify a multidrug-resistance bovine pathogenic Escherichia coli. [Method]The dead cases of calf diarrhea were collected from a large-scale beef cattle farm,and the isolated pathogen was conducted molecular identification,serological identification,drug sensitivity test,and mice pathogenicity test,respectively. Targeted therapy was undertaken thereafter to herds. [Result] One strain of bovine pathogenic E. coli,serotype O101 with strong multidrug resistance and high pathogenicity to mice,was successfully isolated. It was used to develop sensitive drug for timely treating follow-up diarrhea calves,and successfully controlled calf diarrhea in the farm. [Conclusion]The results provide a basis for effective prevention and control of bovine colibacillosis.

关键词： Calf diarrhea Escherichia coli Multidrug resistance Clinical treatment

来源：评论

学校读者我要写书评

暂无评论

近56年连山夏季高温特征分析

引用

清远职业技术学院学报 2018年第5期11卷 25-28页

作者：阮楚雯李少远邓福兴连州市气象局广东连州513400

通过运用1962-2017年连山逐日最高气温资料对连山夏季高温特征的统计分析,可以得出,连山高温日和高温热害事件年变化呈波动上升趋势,大概以0.35d/a和0.37次/10a的速度上升。年均高温日数为10d,年均高温热害事件1.1次,高温日主要集中在5-... 详细信息

通过运用1962-2017年连山逐日最高气温资料对连山夏季高温特征的统计分析,可以得出,连山高温日和高温热害事件年变化呈波动上升趋势,大概以0.35d/a和0.37次/10a的速度上升。年均高温日数为10d,年均高温热害事件1.1次,高温日主要集中在5-9月,高温热害事件只在6-9月出现,且以7、8月最为频繁;用M-K法检测出高温日数在2000年发生了突变。由小波可分析得出连山高温有2个不同时间尺度的周期震荡互相嵌套,分别为准5和准10年。

关键词：高温气候特征小波分析 M-K

来源：评论

学校读者我要写书评

暂无评论

Highly efficient manipulation of Laplace fields in film system with structured bilayer composite

引用

OPTICS EXPRESS 2016年第26期24卷 29537-29546页

作者： Lan, chuwen Lei, Ming Bi, Ke li, Bo Zhou, Ji Tsinghua Univ Sch Mat Sci & Engn State Key Lab New Ceram & Fine Proc Beijing 100084 Peoples R China Tsinghua Univ Shenzhen Grad Sch Adv Mat Inst Shenzhen Peoples R China Beijing Univ Posts & Telecommun State Key Lab Informat Photon & Opt Commun Beijing 100876 Peoples R China Beijing Univ Posts & Telecommun Sch Sci Beijing 100876 Peoples R China Southeast Univ Sch Informat Sci & Engn State Key Lab Millimeter Waves Nanjing 210096 Jiangsu Peoples R China

Using metamaterials or transformation optics to manipulate Laplace fields, such as magnetic, electric and thermal fields, has become a research highlight. These studies, however, are usually limited to a bulk material system and to single field manipulation. In this paper, we focus on a film system and propose a general practical method applicable for such a system. In this method, the background film is covered with another one to construct a so- called "bilayer composite" to achieve required physical parameters. On the basis of the bilayer composite, a multi-physics cloak and a multi-physics concentrator for electric current and thermal flux are designed, fabricated, and demonstrated. This work provides an efficient way to control and manipulate single/multi-physics Laplace fields like a dc electric field and a thermal field in a film system, which may find potential applications in IC technology, MEMS, and so on. (C) 2016 Optical Society of America

关键词： Electric fields Magnetic fields Optical devices Thin film applications Thin films Transformation optics

来源：评论

学校读者我要写书评

暂无评论

Temperature tunable photonic band gap in polyvinylidene fluoride inverse opals

引用

RSC ADVANCES 2016年第108期6卷 106370-106373页

作者： Yao, Jitan Wang, Jin Ji, Muwei Lan, chuwen liu, Wenmei li, Bo Tsinghua Univ Grad Sch Shenzhen Adv Mat Inst Shenzhen 518055 Peoples R China

Inverse polyvinylidene fluoride (PVDF) opals with a temperature tunable photonic band gap (PBG) were fabricated by the sol-gel process using SiO2 opal templates. The samples exhibited an olivine to dark blue color after heat treatment at different temperatures. Their microregion reflection spectra showed that the inverse PVDF opal PBG blue-shifted from 573 nm to 498 nm when the treating temperature increased from 80 degrees C to 160 degrees C. This was due to a reduction of the inverse PVDF opal periodical size during the heat treatment process. Such inverse PVDF opals with temperature tunable PBGs have a great potential in device applications.

关键词： Energy gap

来源：评论

学校读者我要写书评

暂无评论

Structural elucidation of Pogostone and its dimers-two novel diastereomers combined with X-ray diffraction and spectroscopy

引用

JOURNAL OF MOLECULAR STRUCTURE 2014年第1期1058卷 189-196页

作者： Zhao, Xiaoning li, chuwen Cao, Yongkai Yi, Yuyang Shi, Shujiang Feng, Xuexuan Su, Ziren Zeng, Huifang Guangzhou Univ Chinese Med Affiliated Hosp Chinese Med 1 Guangzhou 510405 Guangdong Peoples R China Chonnam Natl Univ Coll Pharm Kwangju 500757 South Korea Chonnam Natl Univ Res Inst Drug Dev Kwangju 500757 South Korea Guangzhou Univ Chinese Med Sch Chinese Mat Med Guangzhou Guangdong Peoples R China

Two new dimers of Pogostone were prepared simultaneously when synthesizing Pogostone. Their molecular structures were elucidated on the basis of spectral interpretation, including FT-IR, H-1 and C-13 NMR, homo-nuclear correlation (COSY), and hetero-nuclear correlation (HMQC and HMBC) together with single crystal X-ray diffraction. Compound 1 crystallized in the orthorhombic P bc n space group with the crystal cell parameters a = 11.24391(16) angstrom, b = 17.7313(3) angstrom, c = 22.6331(4) angstrom, V = 4512.34(12) angstrom(3) and Z = 8. Compound 2 crystallized in the monoclinic P 21/c space group with the crystal cell parameters a = 15.0390(4) angstrom, b = 11.3591(3) angstrom, c = 13.1370(3) angstrom, beta = 94.167(2)degrees, V = 2238.25(10) angstrom(3) and Z = 4. The X-ray results demonstrated there solely existed classic H-bond intramolecular rather than intermolecular interactions in the molecules of the two compounds. Furthermore, regarding the R configuration (compound 1), two pyranone rings were approximately perpendicular to each other (100.614 degrees), whereas for the S configuration (compound 2), two pyrone rings were almost paralleled (7.143 degrees). It had obvious influence on the symmetry of molecule and great different spatial structure and the packing mode. (C) 2013 Elsevier B.V. All rights reserved.

关键词： Crystal structure Pogostone Conformational isomerism Pogostone dimers

来源：评论

学校读者我要写书评

暂无评论

A Flower-Shaped Thermal Energy Harvester Made by Metamaterials

引用

GLOBAL CHALLENGES 2017年第6期1卷 1700017页

作者： liu, Wenmei Lan, chuwen Ji, Muwei Yao, Jitan Wang, Jin li, Bo Zhou, Ji Tsinghua Univ Grad Sch Shenzhen Shenzhen 510085 Peoples R China Tsinghua Univ State Key Lab New Ceram & Proc Beijing 100084 Peoples R China

Harvesting thermal energy from arbitrary directions has become an exciting theoretical possibility. However, an exact 3D thermal energy harvester is still challenging to achieve for the stringent requirement of highly anisotropic and symmetrical structures with homogenous materials, as well as absence of effective characterization. In this Communication, a flower-shaped thermal harvesting metamaterial is originally promoted. Numerical simulations imply that heat flux can be concentrated into the target core and a temperature gradient turns out to be more than two times larger than the applied one without obvious distortion or perturbation to the temperature profile outside the concentrator. Temperature transitions of the actual device are experimentally measured to validate the novel structure with consistency of the simulated results with original methods. With ultraefficiency independent of geometrical size, the flower-shaped thermal harvester facilitates multiple scale energy harvesting with splendid efficient and might help to improve thermoelectric devices efficiency in a totally new perspective.

关键词： conversion energy harvesting metamaterials thermal concentration thermoelectric

来源：评论

学校读者我要写书评

暂无评论

Optimization of culture conditions to improve the expression level of beta1-epsilon toxin of Clostridium perfringens type B in Escherichia coli

引用

BIOTECHNOLOGY & BIOTECHNOLOGICAL EQUIPMENT 2016年第2期30卷 324-331页

作者： lin, chuwen Cheng, likun Wang, Jing Zhang, Songlin Fu, Qiang li, Shuguang li, Feng Han, Wenyu Shen, Zhiqiang Jilin Univ Coll Vet Med Changchun 130023 Peoples R China Shandong Lvdu Biosci & Technol Co Ltd Shandong Binzhou Anim Sci & Vet Med Acad Shandong Binzhou Res Dev & Promot Ctr Livestock & Binzhou Peoples R China Binzhou Med Univ Hosp Intens Care Unit Binzhou Peoples R China

The detoxified beta1-epsilon (beta 1-epsilon) toxin protein of Clostridium perfringens type B provides protection from C. perfringens types B, C and D infections. Acetate is the primary by-product from the cell growth and expression of beta 1-epsilon protein. In the present study, the effects of pH and dissolved oxygen (DO) on the expression of beta 1-epsilon protein were investigated. Two-stage pH and DO control strategies were developed for the expression of beta 1-epsilon protein. The obtained results indicated that higher cell density and concentration of beta 1-epsilon protein, and lower accumulation of acetate were obtained when pH was maintained at a constant level of 6.5 (0-6 h) and 7.0 (6-16 h), and the DO level was maintained at 60% (0-6 h) and 30% (6-16 h). Furthermore, the impact of intermittent, DO feedback, pH feedback and glucose-stat feeding on the expression of beta 1-epsilon protein were studied. By using the DO feedback feeding, combined with the stage control of pH (6.5 for 0-6 h, 7.0 for 6-16 h) and DO (60% for 0-6 h, 30% for 6-16 h), the highest cell density of 2.045 (absorbance at 600 nm) and a beta 1-epsilon protein concentration of 63.24 mg/L were obtained, and the accumulation of acetate decreased to 0.872 g/L.

关键词： Clostridium perfringens beta1-epsilon toxin Escherichia coli pH dissolved oxygen feeding strategy

来源：评论

学校读者我要写书评

暂无评论

Characterisation of the Metabolism of Pogostone In Vitro and In Vivo Using liquid Chromatography with Mass Spectrometry

引用

PHYTOCHEMICAL ANALYSIS 2014年第2期25卷 97-105页

作者： li, Yucui Su, Ziren lin, Shuhai li, chuwen Zhao, Ya Gao, Xiang Lai, Yongquan Wu, Xiaoli Wu, Hanzhi Cai, Zongwei Lai, Xiaoping Guangzhou Univ Chinese Med Coll Chinese Med Guangzhou Higher Educ Mega Ctr Guangzhou 510006 Guangdong Peoples R China Hong Kong Baptist Univ Dept Chem Kowloon Hong Kong Peoples R China Guangzhou Univ Chinese Med Dongguan Math Engn Acad Chinese Med Dongguan 523808 Peoples R China

IntroductionPogostone possesses potent anti-bacterial and anti-fungal activities and has been used for the quality control of essential oil of Pogostemon cablin. Pogostone is easily absorbed after oral administration but its metabolism in mammals remains elusive. ObjectiveTo investigate the metabolic profile of pogostone in vitro and in vivo. MethodsHigh-performance liquid chromatography coupled with mass spectrometry (LC-MS) techniques were employed. Orbitrap MS and ion trap tandem mass spectrometry (MS/MS) were utilised to analyse the metabolism of pogostone by virtue of the high sensitivity and high selectivity in the measurement. In vitro experiment was carried out using rat liver microsomes while the in vivo study was conducted on rats, which were orally administered with pogostone (80mg/kg). ResultsIn total, three mono-hydroxylated, one di-hydroxylated, one mono-oxygenated, one di-oxygenated metabolite, one hydrolysis and one hydroxy conjugated metabolites were found. In addition hydroxylation was demonstrated to be a major metabolic pathway of pogostone. ConclusionLC-MS was demonstrated to be a powerful tool for the metabolite identification of pogostone. The tentative identification of metabolites provides an insight for the metabolic clues of pogostone. Copyright (c) 2013 John Wiley & Sons, Ltd.

关键词： LC-MS hydroxylation orbitrap oxidation metabolites pogostone rat liver

来源：评论

学校读者我要写书评

暂无评论

NEW-TYPE SLURRY ABRASIVE JET SYSTEM

NEW-TYPE SLURRY ABRASIVE JET SYSTEM

引用

作者： GUO, chuwen SHI, Lele liU, Songyong JIANG, Hongxiang WANG, Fengchao FENG, Dachuan li, Fangbing

标准号: WO2018103284(A1)

A slurry abrasive jet system, consisting of a closed-loop hydraulic oil system and an open-loop slurry jet system. The closed-loop hydraulic oil system comprises: a hydraulic oil tank, an oil filter (1), a high-pressure oil pump (2), an electromagnetic directional valve (4, 7, 10), a one-way check valve (5), a high-pressure oil chamber, and a double acting piston (8). The open-loop slurry jet system comprises: a one-way check valve, a slurry pressurizing chamber, a double-acting piston, and an electromagnetic directional valve. The relatively independent slurry chamber and the high-pressure oil chamber effectively prevent a slurry abrasive from mixing with another substance during a pressurization process. The adoption of the double-acting piston effectively solves the problem of intermittent feeding of a slurry jet, thus achieving continuous operation of the slurry jet system.

关键词：

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：