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Lipase-catalyzed synthesis of novel galactosylated cholesterol

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Chinese Chemical Letters 2015年第5期26卷 543-546页

作者： hua nie Yi Cheng Pin-Jing Zheng Li-hua Luo Sheng-Yuan Zhang Medical College of Jiaying University College of Traditional Chinese Medicine Guangzhou University of Chinese Medicine

In an organic phase system, an enzymes lipase was used as a catalyst to synthesize galactosylated cholesterol, （5-cholesten-3b-yl）[（4-O-/%u-galactopyranosyl）u-glucitol-6] sebacate （CHS-SE-LA）, which contains galactose residues. Its chemical structure was characterized by ESI-MS, and NMR. For HepG2 cells, the cellular fluorescence intensities of liposomes modified with CHS-SE-LA （GAL-FL） were as much as 2.6-fold （p 〈 0.01） control liposomes （FL）. Moreover, the presence of excess galactose significantly inhibited the uptake of GAL-FL suggesting ASGPR mediated uptake. In conclusion, the novel galactosylated ligand CHS-SE-LA was synthesized by lipase-catalyzation and revealed a great potential as drug carrier materials for hepatocyte-selective targeting.

关键词： Cholesterol derivative Liposomes Asialoglycoprotein receptor Lipase-catalyzed

Assay of Cysteine in Human Serum with Quinine-Ce^(4+) Chemiluminescence System

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Chinese Chemical Letters 2002年第10期13卷 977-978页

作者： Li hua nie Hui Min MA Mei Hong SU Ming SUN Xiao hua LI Center for Molecular Sciences Institute of ChemistryChinese Academy of SciencesBeijing 100080

A sensitive and selective chemiluminescence (CL) method was developed for the determination of cysteine. This method is based on that the weak CL of cysteine oxidized with cerium (IV) can be greatly enhanced by quinine, and the total cysteine in human serum can be detected through simply diluting with water, showing a simpler analytical characteristic.

关键词： chemiluminescence cysteine quinine-Ce4+ system human serum

A virtual machine-based invasion detection system for the virtual computing environment

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High Technology Letters 2006年第4期12卷 379-384页

作者：曾宇 Wang Jie Sun Ninghui Li Jun nie hua Research and Development Center for National Intelligence Computing System Institute of Computing Technology Chinese Academy of Sciences Beijing 100080 P.R. China Key Laboratory of Computer System and Architecture Institute of Computing Technology Chinese Academy of Sciences Beijing 100080 P.R. China

Under virtualization idea based on large-scale dismantling and sharing, the implementing of network interconnection of calculation components and storage components by loose coupling, which are tightly coupling in traditional server, achieves computing capacity, storage capacity and service capacity distri- bution according to need in application-level. Under the new server model, the segregation and protection of user space and system space as well as the security monitoring of virtual resources are the important factors of ultimate security guarantee. This article presents a large-scale and expansible distributed invasion detection system of virtual computing environment based on virtual machine. The system supports security monitoring management of global resources and provides uniform view of security attacks under virtual computing environment, thereby protecting the user applications and system security under capacity services domain.

关键词： virtual computing environment oriented virtual machine-based invasion detection system (VIDS) capacity services computing

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组团式城市快速路网布局思路

交通企业管理 2024年第3期39卷 98-101页

作者：田伦聂华波骆中林中交第二公路勘察设计研究院有限公司

随着我国城市化和机动化水平的不断提升,城市道路交通拥堵成为制约城市社会经济快速发展的重要因素。尤其是对于组团式空间结构布局的城市而言,组团间交通联系集中于有限的通道资源内,极易造成组团间道路交通供需失衡。而快速路作为城... 详细信息

随着我国城市化和机动化水平的不断提升,城市道路交通拥堵成为制约城市社会经济快速发展的重要因素。尤其是对于组团式空间结构布局的城市而言,组团间交通联系集中于有限的通道资源内,极易造成组团间道路交通供需失衡。而快速路作为城市干线道路的重要组成,承担城市中长距离联系交通,是支撑城市交通高质量发展的关键抓手。在《国家综合立体交通网规划纲要(2021—2050年)》中也提出“推动城市道路网结构优化,形成级配合理、接入顺畅的路网系统”。由此,开展组团式空间结构布局城市的快速路网体系研究对支撑城市经济社会发展具有重要意义。

关键词：城市快速路路网规划组团式城市空间结构客流分布特征布局思路漳州市

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Application of calcium alumino-titanate to taphole clay

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Journal of Iron and Steel Research International 2022年第7期29卷 1089-1100页

作者： Mao-qi Ju Man-fei Cai Yong-he Liang Jian-hua nie Meng-zhen Guo The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina

Calcium alumino-titanate(CAT)can be used as a raw material owing to its excellent refractoriness and thermal ***-containing taphole clay(THC)with different particle sizes was prepared and *** results indicated that THC with CAT aggregate has better thermo-mechanical performance than that with a fine CAT powder because of different sintering *** CAT aggregate and SiO_(2)reacted and formed liquid phase covering their surface,enhancing the bonding of the particle–matrix and promoting the internal transformation of the ***,the mullite was formed in aggregate with the interwoven network *** CAT powder has a higher specific surface area,and its surface energy decreases with the particle *** could cause a reaction between CAT and SiO_(2)at relatively low temperature,making it unable to form a core–shell structure similar to that of the aggregate,with the excessive liquid phase affecting the performance of the ***,the liquid phase was formed to close the pores and cover the SiC surface,and this was found to enhance the oxidation resistance.A corrosion test confirmed that the THC refractories with CAT aggregates showed better corrosion resistance than other *** electron microscopy and energy-dispersive spectrometry results indicated that Ti(C,N)transformed by TiO_(2)in CAT was deposited at the interface between the molten slag and the refractory,and it efficiently prevented the penetration and reaction owing to its high melting point and small wetting angle with the slag.

关键词： Taphole clay Calcium alumino-titanate Microstructure Corrosion resistance

Synthesis and Phase Behavior of Poly(1-alkyne) with Liquid Crystalline-induced Luminescence Enhancement

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Chemical Research in Chinese Universities 2010年第6期26卷 1035-1044页

作者： ZHOU Dan CHEN Yi-wang CHEN Lie LI Fan nie hua-rong YAO Kai Institute of Polymers Department of Chemistry Nanchang University Nanchang 330031 P. R. China

Poly（1-alkyne） with octoxy spacer —{[HC=C（CH2）8O—terphenyl—CN]}n—（PA8CN） and terphenyl liquid crystalline pendant was synthesized,and the effects of structure on the optical properties,especially the liquid crystallinity behavior of the polymer and monomer were *** monomer was prepared in high yields（92.30%） by coupling and etherification reactions and successfully polymerized in the presence of Rh catalyst and Et3N cocatalyst in high yields with trans-rich（86.27%） stereoregular *** to the monomer showing mixed monolayer structure,its corresponding polymer PA8CN formed homogeneous monolayer *** photoexcitation,strong blue emission peak of PA8CN appeared at 413 nm[fluorescence quantum yield,ΦF = 68% when excited at 330 nm in tetrahydrofuran（THF） solution].Compared with its solid film photoexcitated at 330 nm at room temperature,the UV light-emitting band of PA8CN solid film from its liquid crystalline with liquid nitrogen quenched rapidly at 236 ℃ was red-shift 10 nm with higher intensity,which may be ascribed to the fact that the effectual conjugation and the order degree of the molecule in the liquid crystalline state of the polymer were enhanced,the energy loss caused by the thermal vibration was decreased,thus resulting in the observed hyperchromic effect.

关键词： Polyacetylene Liquid crystallinity Phase transition Photoluminescence

Atomically constructing a van der Waals heterostructure of CrTe_(2)/Bi_(2)Te_(3) by molecular beam epitaxy

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Materials Futures 2023年第2期2卷 1-7页

作者： Jin-hua nie Rui Li Mao-Peng Miao Ying-Shuang Fu Wenhao Zhang School of Physics and Wuhan National High Magnetic Field Center Huazhong University of Science and TechnologyWuhan 430074People’s Republic of China

A 2D heterostructure with proximity coupling of magnetism and topology can provide enthralling prospects for hosting new quantum states and exotic properties that are relevant to next-generation spintronic ***,we synthesize a delicate van der Waals(vdW)heterostructure of CrTe_(2)/Bi_(2)Te_(3) at the atomic scale via molecular beam ***-temperature scanning tunneling microscopy/spectroscopy measurements are utilized to characterize the geometric and electronic properties of the CrTe_(2)/Bi_(2)Te_(3) heterostructure with a compressed vdW *** structural analysis reveals complex interfacial structures with diversiform step heights and intriguing moiré*** formation of the interface is ascribed to the embedded characteristics of CrTe_(2) and Bi_(2)Te_(3) by sharing Te atomic layer upon interfacing,showing intercoupled features of electronic structure for CrTe_(2) and Bi_(2)Te_(3).Our study demonstrates a possible approach to construct artificial heterostructures with different types of ordered states,which may be of use for achieving tunable interfacial Dzyaloshinsky–Moriya interactions and tailoring the functional building blocks in low dimensions.

关键词： molecular beam epitaxy scanning tunneling microscopy/spectroscopy 2D heterostructure interfacial structures

Impact of backwater on water surface profile in curved channels

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Water Science and Engineering 2023年第3期16卷 295-301页

作者： Rui-hua nie Qi-hang Zhou Wen-jie Li Xing-nian Liu Gang Xie Lu Wang State Key Laboratory of Hydraulics and Mountain River Engineering College of Water Resource and HydropowerSichuan UniversityChengdu 610065China National Engineering Research Center for Inland Waterway Regulation Chongqing Jiaotong UniversityChongqing 400074China China Institute of Water Resources and Hydropower Research Beijing 100048China

Owing to extensive construction of dams, the impact of backwater on flow may lead to navigation or flood control issues in curved channels. To date, the impact of backwater on the water surface profile in curved channels remains unknown and requires investigation. In this study, experiments were conducted in a glass-walled recirculating flume with a length of 19.4 m, a width of 0.6 m, and a depth of 0.8 m, and the impact of backwater on the water surface profile in a 90° channel bend was investigated. The experimental results showed that the backwater degree had a significant impact on the transverse and longitudinal flow depth distributions in the bend. The transverse slope of the flow (Jr) increased linearly with an increase in the Froude number of the approach flow upstream of the bend. Jr increased with the longitudinal location parameter ξ when −0.2 < ξ < 0.5, and decreased with ξ when 0.5 < ξ < 1.2. Furthermore, the results showed that Jr asymptotically decreased to zero with an increase in the degree of backwater. An equation was formulated to estimate the transverse slope of the flow in a 90° bend in backwater zones.

关键词： Backwater Curved channel Experimental model Transverse slope Water surface profile

Convergence analysis for complementary-label learning with kernel ridge regression

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Applied Mathematics(A Journal of Chinese Universities) 2024年第3期39卷 533-544页

作者： nie Wei-lin WANG Cheng XIE Zhong-hua School of Mathematics and Statistics Huizhou UniversityHuizhou 516007China School of Computer Science and Engineering Huizhou UniversityHuizhou 516007China

Complementary-label learning(CLL)aims at finding a classifier via samples with complementary *** data is considered to contain less information than ordinary-label *** transition matrix between the true label and the complementary label,and some loss functions have been developed to handle this *** this paper,we show that CLL can be transformed into ordinary classification under some mild conditions,which indicates that the complementary labels can supply enough information in most *** an example,an extensive misclassification error analysis was performed for the Kernel Ridge Regression(KRR)method applied to multiple complementary-label learning(MCLL),which demonstrates its superior performance compared to existing approaches.

关键词： multiple complementary-label learning partial label learning error analysis reproducing kernel Hilbert spaces