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Production and Properties of a Thickener with Ability of Suspending Sand

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Journal of China University of Mining and Technology 2006年第2期16卷 115-118,122页

作者： QIN Bo-tao WANG De-ming LI Zeng-hua chen jian-hua School of Mineral and Safety Engineering China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

To overcome the shortcomings of pouring sands, a thickener with the ability to suspend sands was developed. It is mixed with sands to form densified slurry, and can insure the sands against deposition, jamming pipelines and de- hydration. The chemical structure of the thickener is introduced in this paper and the production process is studied. The main processes include immersion, decomposition, dilution and addition of additives. In order to produce a thickener with high viscosity to suspend sands, key factors must be controlled in each process: the immersion time is 2 h; the mass fraction of formaldehyde is 0.01% and mass of NaCO3 accounts for 15% of dry material; the water temperature is 65 ℃ in summer and 72 ℃ in winter and the decomposition time is 2 h in the reaction; the densified decomposition so- lution should be diluted to 1% mass fraction; the additives of calcium ions and pH indicators must be added to the di- luted liquid; the mass fraction of CaCl2 is 0.048% and the pH value of the solution is 7.5. The thickener is a gel with three-dimensional network structure, a liquid with non-Newtonian behaviour and the characteristics of pseudo-plastic material, a solution with little resistance and the ability to revive its oral primary viscosity. It has been successfully ap- plied in Shendong Mines and has great value and wide-spread prospective use.

关键词： thickener ability of suspending sand spontaneous combustion of coal

Research of Trap and Electron Density Distributions in the Interface of Polyimide/Al2O3 Nanocomposite Films Based on IDC and SAXS

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Chinese Physics Letters 2017年第4期34卷 116-119页

作者： Yuan-Yuan Liu Jing-hua Yin Xiao-Xu Liu Duo Sun ming-hua chen Zhong-hua Wu Bo Su Key Laboratory of Engineering Dielectric and Its Applications (Ministry of Education) Harbin University of Science and Technology Harbin 150080 Harbin Cambridge College Harbin 150069 Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049

The distributions of traps and electron density in the interfaces between polyimide （PI） matrix and Al2O3 nanoparticles are researched using the isothermal decay current and the small-angle x-ray scattering （SAXS） tests. According to the electron density distribution for quasi two-phase mixture doped by spherical nanoparticles, the electron densities in the interfaces of PI/Al2O3 nanocomposite films are evaluated. The trap level density and carrier mobility in the interface are studied. The experimental results show that the distribution and the change rate of the electron density in the three layers of interface are different, indicating different trap distributions in the interface layers. There is a maximum trap level density in the second layer, where the maximum trap level density for the nanocomposite film doped by 25 wt% is 1.054 × 10^22 eV·m^-3 at 1.324eV, resulting in the carrier mobility reducing. In addition, both the thickness and the electron density of the nanocomposite film interface increase with the addition of the doped Al2O3 contents. Through the study on the trap level distribution in the interface, it is possible to further analyze the insulation mechanism and to improve the performance of nano-dielectric materials.

关键词： AI PI Research of Trap and Electron Density Distributions in the Interface of Polyimide/Al2O3 Nanocomposite Films Based on IDC and SAXS IDC Al

Adaptive PMD compensation experiment in 40 Gb/s CSRZ system

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Optoelectronics Letters 2007年第3期3卷 207-210页

作者： ZHANG Qi chen ming-hua chen Hong-wei ZHANG Ji-yu Department of Electronic Engineering Tsinghua Univ. Beijing 100084 China

In 40 Gb/s systems with low polarization-mode dispersion(PMD) fibers,first-order PMD is the dominate factor with quite small value. An adaptive PMD compensator consisting of an electrical polarization controller(PC) ,a section of polariza-tion maintaining fiber(PMF) ,a degree of polarization(DOP) detector and a feedback control module is employed in 40 Gb/s NSFCNet. This compensator has a simple structure and high speed,which can compensate up to 20 ps first-order PMD adaptively and the average searching time is 2 ms.

关键词：自适应PMD补偿器补偿实验 CSRZ系统一阶PMD 光纤极化

Trial Production of Sulphurous Free-Cutting Gear Steel by Convert-Billet Continuous Casting Process

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Journal of Iron and Steel Research International 2011年第S2期18卷 394-398页

作者： chen Liang, chen Tian-ming, ZENG Jian-hua, chen Yong (Pangang Group Research Institute Co, Ltd, chengdu 611731, Sichuan, China) Pangang Grp Res Inst Co Ltd Chengdu 611731 Sichuan Peoples R China

In consideration of the composition characteristics and quality requirements of sulphurous free-cutting gear steel, the rational measures of sulfur control, calcium treatment and key technologies of continuous casting process are applied in the development of a full-line operation of LD-Billet continuous casting on steelmaking with semi-steel, which suggests an economic production of the steel has been realized. Test results show that the average retrieval rate of sulphurous alloy in the process of RH treatment is 95.3% and sulfur content of products is stability. Otherwise, content of T[O] in casting billet is in the range of 11×10-6 ~ 18×10-6 with average value is 14.7×*** on this, the billets have good surface quality and internal quality.

关键词： free-cutting gear steel billet continuous casting sulphurous iron

Antiviral stereoisomers of 3,5-bis(2-hydroxybut-3-en-1-yl)-1,2,4-thiadiazole from the roots of Isatis indigotica

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Chinese Chemical Letters 2016年第5期27卷 643-648页

作者： ming-hua chen Sheng Lin Ya-Nan Wang cheng-Gen Zhu Yu-huan Li Jian-Dong Jiang Jian-Gong Shi State Key Laboratory of Bioactive Substance and Function of Natural Medicines Institute of Materia Medica Chinese Academy of Medical Sciences and Peking Union Medical College Institute of Medicinal Biotechnology Chinese Academy of Medical Sciences and Peking Union Medical College

Four stereoisomers of 3,5-bis（2-hydroxybut-3-en-1-yl）-l,2,4-thiadiazole, named insatindigothiadia- zoles A-D （1a-1d）, were isolated from the roots oflsatis indigotica. Their structures were determined by spectroscopic analysis; specifically, the absolute configurations were assigned by using the MPA determination rule based on △δrs values of MPA esters, and supported by electronic CD （ECD） calculations. Proposed biosynthetic pathways and preliminary investigations of the biological activities of la-1d against influenza virus A （H3N2）, Coxsackie virus B3, and/or HSV-1 are also discussed.

关键词： Isatis indigoticaCruciferae3.5-Bis( 2-hydroxybut-3-en- 1 -yl)-1 2 4-thiadiazole Stereoisomer Insatindigothiadiazoles A-DAntiviral activity

Principles and applications of high-speed single-pixel imaging technology

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Frontiers of Information Technology & Electronic Engineering 2017年第9期18卷 1261-1267页

作者： Qiang GUO Yu-xi WANG Hong-wei chen ming-hua chen Si-gang YANG Shi-zhong XIE Tsinghua National Laboratory for Information Science and Technology Department of Electronic Engineering Tsinghua University Beijing 100084 China

Single-pixel imaging （SPI） technology has garnered great interest within the last decade because of its ability to record high-resolution images using a single-pixel detector. It has been applied to diverse fields, such as magnetic resonance imaging （MRI）, aerospace remote sensing, terahertz photography, and hyperspectral imaging. Compared with conventional silicon-based cameras, single-pixel cameras （SPCs） can achieve image compression and operate over a much broader spectral range. However, the imaging speed of SPCs is governed by the response time of digital mieromirror devices （DMDs） and the amount of com- pression of acquired images, leading to low （ms-level） temporal resolution. Consequently, it is particularly challenging for SPCs to investigate fast dynamic phenomena, which is required commonly in microscopy. Recently, a unique approach based on photonic time stretch （PTS） to achieve high-speed SPI has been reported. It achieves a frame rate far beyond that can be reached with conventional SPCs. In this paper, we first introduce the principles and applications of the PTS technique. Then the basic archi- tecture of the high-speed SPI system is presented, and an imaging flow cytometer with high speed and high throughput is demonstrated experimentally. Finally, the limitations and potential applications of high-speed SPI are discussed.

关键词： Compressive sampling Single-pixel imaging Photonic time stretch Imaging flow cytometry

Effect of acute alcoholism on hepatic enzymes and oxidation/antioxidation in rats

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Hepatobiliary & Pancreatic Diseases International 2004年第2期3卷 241-244页

作者： You-ming Li, Shao-hua chen, Chao-Hui Yu, Yu Zhang and Gen-Yun Xu Hangzhou, China Department of Digestive Medicine, First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310003 . Chi- na Department of Digestive Medicine First Affiliated Hospital Zhejiang University School of Medicine Hangzhou 310003 China.

BACKGROUND: Around the world more and more people suffer from acute alcoholism. The purpose of this study was to determine hepatic enzymes and oxidation/antioxidation in rats with acute alcoholism. METHODS: Rats were randomly divided into three groups; control, low-dose alcohol, and high-dose alcohol. Each al- cohol group ( n = 12) was intravenously infused with etha- nol at a dose of 0.3 or 0.7 g/kg body weight respectively. The control group (n =11) was intravenously infused with normal saline at a dose of 0.5 g/kg body weight. Blood was collected for detection of hepatic enzymes and index of oxidation/antioxidation. RESULTS: The ratio of AST to ALT was 2.44±0.46, 2.57± 0.60 and 3.03 ±0.46 in the three groups, and the difference was significant between the control and high-dose alcohol groups (P^0.05). No significant changes were observed in the levels of serum alanine aminotransferase (ALT), aspar- tate aminotransferase (AST), total protein (Tp), albumin (Alb), alkaline phosphatase (ALP), cholinesterase (ChE), total bilirubin (TB), C-reactive protein (CRP) and amy- lase. The levels of serum nitric oxide (NO) in the 3 groups were 39.2 ±73.25 mol/L, 42.30 ±4.60 mol/L and 47.86± 4.66 mol/L, and significant difference was seen between the control group and the high-dose alcohol group (P < 0.01). No significant difference was found in the levels of serum superoxide dismutase (SOD), glutathione (GSH), malondiethylaldehyde (MDA), and CRP in the 3 groups. CONCLUSION: The ratio of AST to ALT appears to be a useful index for acute alcohol intoxication. NO is involved in the mechanism of acute alcohol intoxication.

关键词： alcoholism infusion nitric oxide oxidation/antioxidation animal model hepatic enzyme

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超临界二氧化碳染色技术

丝绸 2001年第10期38卷 23-25页

作者：吴明华陈水林浙江工程学院材料与纺织学院浙江杭州310033 东华大学上海200051

阐述了无污染、低能耗的超临界二氧化碳流体性能及其染色技术的优点和发展现状。

关键词：超临界二氧化碳合成纤维天然纤维发展染色技术

Palladium installed copper-organic framework for C–C coupling reactions

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Science China Chemistry 2025年

作者： Yu-Mei Wang Mei-Xia Tao Kai-ming Mo Xu chen Shu-hua Zhong Elena S Shubina Guo-Hong Ning Dan Li College of Chemistry and Materials Science Guangdong Provincial Key Laboratory of Supramolecular Coordination ChemistryJinan University A.N.Nesmeyanov Institute of Organoelement Compounds Russian Academy of Sciences

The formation of C–C bonds is a crucial aspect of organic synthesis. Synthesists' long-term objective is to identify novel catalysts to optimize reaction systems based on traditional transition metal catalysis. This study explores the synthesis and catalytic potential of palladium-installed covalent metal-organic frameworks(CMOFs) based on copper cyclic trinuclear units(Cu-CTUs). By incorporating palladium ions into the imine-based framework JNM-7 through a straightforward immersion method, we achieved a notable enhancement in catalytic activity for critical C–C coupling reactions, including C–H arylation and Sonogashira cross-coupling. The resulting JNM-7-Pd demonstrated remarkable stability and recyclability, maintaining its efficiency over at least three cycles without any decline in efficiency.

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