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Efficient hydrolysis of hemicellulose to furfural by novel superacid SO_4H-functionalized ionic liquids

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Green Energy & Environment 2019年第1期4卷 49-55页

作者： wei hui yan Zhou yan Dong Zhi-Jun Cao Fei-Qiang he Min-zhong cai Duan-Jian tao College of Chemistry and Chemical Engineering Institute of Advanced Materials Jiangxi Normal University

Novel superacid SO_4H-functionalized ionic liquids(SFILs) were designed and prepared in this work. The catalytic activities of SFILs were evaluated in xylan hydrolysis and xylose dehydration to produce furfural. Combined with the results of acid strength of SFILs characterized by solid-state ^(31)P MAS NMR, it was found that the catalytic performance of SFILs was positively correlated to their acid strength. The superacid SFIL [Ch-SO_4H][CF_3SO_3] displayed the best catalytic performance with more than 80% yield of furfural, and it was also obviously superior to usual SO_3H-functionalized acidic ILs, mineral liquid acids, and acidic resin Amberlyst-15 catalysts in catalytic activity under optimized conditions. In addition, the superacid SFIL [Ch-SO_4H][CF_3SO_3] could be easily separated from reaction system and reused at least five times without obvious decrease.

关键词： Superacid Ionic liquids hemicellulose Hydrolysis Furfural

Longitudinal surface cracks of thin slabs

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International Journal of Minerals,Metallurgy and Materials 2010年第2期17卷 159-166页

作者： yan-hui Sun You-jin Ni Hai-tao Wang zhong-bo Xu Kai-ke cai School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing 100083 China

Based on the production practice of medium carbon thin slabs in the CSP plant,the reasons and influencing factors for the formation of longitudinal cracks were investigated,and some industrial measures were taken to eliminate the *** results show that the efficient solutions to reduce longitudinal cracks are improving the performance of the mold powder,stabilizing the mold heat flux,and maintaining a proper taper of the mold during *** pouring temperature and secondary cooling also play important roles in preventing longitudinal surface cracks.

关键词： CSP thin slab medium carbon steel surface cracks

Numerical simulation of low-Reynolds number flows past two tandem cylinders of different diameters

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Water Science and Engineering 2013年第4期6卷 433-445页

作者： Yong-tao WANG zhong-min yan hui-min WANG College of Environmental Science and Engineering Suzhou University of Science and Technology College of Water Conservancy and Hydropower Engineering Hohai University College of Environment Hohai University

The flow past two tandem circular cylinders of different diameters was simulated using the finite volume method. The diameter of the downstream main cylinder （D） was kept constant, and the diameter of the upstream control cylinder （d） varied from 0.1D to D. The studied Reynolds numbers based on the diameter of the downstream main cylinder were 100 and 150. The gap between the control cylinder and the main cylinder （G） ranged from 0.1D to 4D. It is concluded that the gap-to-diameter ratio （G/D） and the diameter ratio between the two cylinders （d/D） have important effects on the drag and lift coefficients, pressure distributions around the cylinders, vortex shedding frequencies from the two cylinders, and flow characteristics.

关键词： two tandem cylinders vortex shedding drag force lift force numerical simulation

Simulation of hard–soft material interaction under impact loading employing the material point method

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Science China(Technological Sciences) 2015年第4期58卷 763-768页

作者： LIU Han tao JIANG Shan CheN Zhen GAN Yong chang Jian zhong WANG yan Hua TONG Zhi hui Laboratory of Energy & Environment and Computational Fluid Dynamics North University of China Department of Civil and Environmental Engineering University of Missouri School of Aeronautics and Astronautics Zhejiang University

Understanding the mechanisms of hard–soft material interaction under impact loading is important not only in the defense industry but also in daily ***,traditional mesh-based spatial discretization methods that are time consuming owing to the need for frequent re-meshing,such as the finite element method and finite difference method,can hardly handle large deformation involving failure evolution in a multi-phase interaction *** objective of this research is to develop a quasi-meshless particle method based on the material point method for the model-based simulation of the hard–soft material interaction *** demonstrate the proposed procedure,scenarios of a hard–soft material impact test are considered,where a force is applied to layers of materials and a hard bar with an initial velocity impacts a target with layers of different *** stress wave propagation and resulting failure evolution are simulated and compared with available *** research tasks are then discussed on the basis of the preliminary results.

关键词： material point method hard--soft materials impact quasi-meshless particle method

Association between gestational anemia in different trimesters and neonatal outcomes:a retrospective longitudinal cohort study

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World Journal of Pediatrics 2021年第2期17卷 197-204页

作者： chang-Fa Sun Han Liu yan-hui hao Hong-tao Hu Zhi-yang Zhou Ke-Xin Zou Xin-Mei Liu Jian-zhong Sheng Guo-Lian Ding he-Feng Huang The International Peace Maternity and Child health Hospital School of MedicineShanghai Jiao Tong University910 Hengshan RoadShanghai 200030China Shanghai Key Laboratory of Embryo Original Diseases ShanghaiChina Department of Pathology and Pathophysiology School of MedicineZhejiang UniversityHangzhouChina Department of Gynecology and Obstetrics The First Affiliated Hospital of Nanjing Medical UniversityNanjingChina

Background Previous studies investigated the association between gestational anemia and neonatal ***,few studies explored whether the effects of gestational anemia could be eliminated by subsequent correction of anemia in the later stages of *** study aimed to investigate the relationship between anemia in different trimesters and neonatal *** The study was conducted in Shanghai,China,with a sample of 46,578 pregnant women who delivered between January 1,2016 and July 1,2019.A multivariable logistic regression model was adopted to analyse the associations between maternal anemia and neonatal *** The incidence of gestational anemia was 30.2%,including 4.4%in the first trimester,9.6%in the second trimester,and 16.2%in the third *** 24.5%(507/2066)of anemia that occurred in the first trimester and 29.6%(1320/4457)that occurred in the second trimester could be corrected in the later stages of *** occurring in the first trimester was associated with small for gestational age[odds ratio(OR)1.46;95%confidence interval(CI)1.20-1.78]and with fetal distress(OR 1.23;95%CI 1.08-1.40).Anemia corrected in the first trimester also was associated with a higher risk of small for gestational *** Gestational anemia is a public health problem in China impacting neonatal *** in pregnancy could be corrected in only about a quarter of the *** in the first trimester,whether corrected or not,still led to lower birth weight;therefore,the prevention of anemia prior to pregnancy is important.

关键词： hemoglobin Iron deficiency Low birth weight Preterm birth Small for gestational age

Industrial Experiment of Reducing Superheat of Steel by Nozzle Cooling

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Journal of Iron and Steel Research International 2011年第6期18卷 22-25页

作者： yan hui-cheng QIU Sheng-tao TONG Tai-qin cai Yun-teng WANG zhong-ying Zhao Pei State Key Laboratory of Advanced Steel Processing and Products Central Iron and Steel Research Institute Beijing 100081 China National Engineering Research Center of Continuous Casting Technology Central Iron and Steel Research Institute Eeijing 100081 China Huai Special Steel Co L.td Shasteel Group Huaian 211600 Jiangsu China

Nozzle cooling equipment is developed to supervise and control the heat flux by changing water flux. An in- dustrial experiment is held in billet caster in Huaigang . The results show that cooling control system works stably and effectively to control the heat fluxes by the temperature of copper tube. The superheat of steel in mould is reduced and the equiaxed crystal ratio, as well as compact degree of steel is raised.

关键词： nozzle cooling low superheat industrial experiment

Synthesis and Properties of SEPS-g-PEO Copolymers with Varying Branch Lengths

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Chinese Journal of Polymer Science 2018年第8期36卷 934-942页

作者： zhong-Fu Zhao Pei-Ying Liu Chun-Qing Zhang wei Liu yan-hui Wang tao Tang Yi-Fu Ding yan-Dong Zhang Fan-Zhi Meng State Key Laboratory of Fine Chemicals School of Chemical EngineeringDalian University of Technology State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of Sciences Department of Mechanical Engineering University of Colorado Boulder

Poly（ethylene oxide）（PEO） was controllably grafted from styrene-b-（ethylene-co-propylene）-b-styrene （SEPS） backbones by combining lithiation of styrenic units and living monomer-activated anionic ring-opening polymerization of ethylene oxide （EO） monomers with the aid of co-initiators triisobutyl aluminum. The as-synthesized SEPS-g-PEO copolymers were characterized by SEC, 1H-NMR, FTIR, SAXS, AFM and DSC. When the branch length is relatively small, increase of PEO fraction leads to the increase of the correlation length between neighboring hard domains, but the degree of correlation reduces. When the branch length is relatively large, the phase-separated structures become random both in terms of size and spatial correlation, and macro-phase separated structures appear. The crystallization behavior of the PEO branches can be effectively inhibited in SEPS-g-PEO, so no significant crystallization takes place until the fraction of PEO branches is 20.1 wt%, which greatly promotes the rapid delivery of hydrophilic drugs in the hot-melting pressure- sensitive adhesives （HMPSAs） based on SEPS-g-PEO. Their cumulative release amount of a model drug could achieve 80%, more than twice the value in the HMPSAs based on linear PEO-containing styrenic block copolymers.

关键词： Living anionic polymerization SEPS-g-PEO copolymers Phase structures Drug delivery

Triterpenoid saponins from the roots of Cyathula officinalis and their inhibitory effects on nitric oxide production

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Chinese Journal of Natural Medicines 2017年第6期15卷 463-466页

作者： JIANG Yun-tao yan Wen-Jing QI Chu-Lu HOU Ji-Qin zhong yan-Ying LI hui-Jun WANG hao LI Ping State Key Laboratory of Natural Medicines China Pharmaceutical University Nanjing 210009 China Department of Natural Medicinal Chemistry China Pharmaceutical University Nanjing 210009 China

The present study was designed to investigate the chemical constituents of the roots of Cyathula officinalis. Compounds were isolated by silica gel, Sephadex LH-20, ODS column chromatography, and preparative HPLC. Their structures were determined on the basis of 1D and 2D NMR techniques, mass spectrometry, and chemical methods. One new oleanane-type triterpenoid saponin, 28-O-[α-L-rhamnopyranosyl-(1→3)-β-D-glucuronopyranosyl-(1→3)-β-D-glucopyranosyl] hederagenin(1), was isolated from the roots of Cyathula officinalis. The anti-inflammatory activities of the isolates were evaluated for their inhibitory effects against LPS-induced nitric oxide(NO) production in RAW 264.7 macrophages cells. Compounds 2, 4, and 6 exhibited moderate anti-inflammatory activities.

关键词： Cyathula officinalis Amaranthaceae Triterpenoid saponins Nitric oxide inhibition

Nitrogen doping/infusion of 650 MHz cavities for CEPC

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Nuclear Science and Techniques 2021年第5期32卷 17-23页

作者： Peng Sha Jian-Kui hao wei-Min Pan Lin Lin Hong-Juan Zheng Xin-Ying Zhang Fang Wang Ji-Yuan zhai Zheng-hui Mi Fei-Si he Shu Chen Bai-Qi Liu Zhi-tao yang Chao Dong zhong-Quan Li State Key Laboratory of Nuclear Physics and Technology&Institute of heavy Ion Physics Peking UniversityBeijing 100871China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China Key Laboratory of Particle Acceleration Physics and Technology Chinese Academy of SciencesBeijing 100049China Center for Superconducting RF and Cryogenics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China

The nitrogen doping/infusion of 650 MHz cavities for the circular electron positron collider(CEPC)is investigated in this *** 650 MHz 1-cell cavities are first treated via buffered chemical polishing(BCP),followed by nitrogen doping.A"2/6"condition is adopted,similar to that for 1.3 GHz cavities of Linear Coherent Light Source *** quality factor of both cavities improved to 7×10^(10)in low fields,i.e.,higher than that obtained from the baseline *** 650 MHz two-cell cavity is nitrogen infused at 165℃for 48 h with a BCP surface *** intrinsic quality factor(Q0)reached6×10^(10)at 22 MV/m in the vertical test,and the maximum gradient is 25 MV/m,which exceeds the specification of the CEPC(4×10^(10)at 22 MV/m).

关键词： Superconducting radio frequency cavity Nitrogen doping Nitrogen infusion Quality factor Accelerating gradient