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| 1 | Synthesis, isolation and characterization of methyl levulinate from cellulose catalyzed by extremely low concentration acid显示文摘A direct synthesis of methyl levulinate from cellulose alcoholysis in methanol medium under mild condition(180 210 C)catalyzed by extremely low concentration sulfuric acid(0.01 mol/L)and the product isolation were developed in this study.Effects of different process variables towards the catalytic performance were performed as a function of reaction time.The results indicated that sulfuric acid concentration,temperature and initial cellulose concentration had significant effects on the synthesis of methyl levulinate.An optimized yield of around 50%was achieved at 210 C for 120 min with sulfuric acid concentration of 0.01 mol/L and initial cellulose concentration below 100 g/L.The resulting product mixture was isolated by a distillation technique that combines an atmospheric distillation with a vacuum distillation where n-dodecane was added to help distill the heavy fraction.The light fraction including mainly methanol could be reused as the reaction medium without any substantial change in the yield of methyl levulinate.The chemical composition and structural of lower heavy fraction were characterized by GC/MS,FTIR,1H-NMR and13C-NMR techniques.Methyl levulinate was found to be a major ingredient of lower heavy fraction with the content over 96%.This pathway is efficient,environmentally benign and economical for the production of pure levulinate esters from cellulose. | Hui Li Lincai Peng Lu Lin Keli Chen Heng Zhang | 2013 | Journal of Energy Chemistry2013，22，6： | 9 |
| 2 | Novel Surface Design of Deployable Reflector Antenna Based on Polar Scissor Structures显示文摘Space-deployable mechanisms can be used as supporting structures for large-diameter antennas in space engineering.This study proposes a novel method for constructing the surface design of space reflector antennas based on polar scissor units.The concurrency and deployability equations of the space scissor unit with definite surface constraints are derived using the rod and vector methods.Constraint equations of the spatial transformation for space n-edge polar scissor units are summarized.A new closed-loop deployable structure,called the polar scissor deployable antenna(PSDA),is designed by combining planar polar scissor units with spatial polar scissor units.The overconstrained problem is solved by releasing the curve constraint that locates at the end-point of the planar scissor mechanism.Kinematics simulation and error analysis are performed.The results show that the PSDA can effectively fit the paraboloid of revolution.Finally,deployment experiments verify the validity and feasibility of the proposed design method,which provides a new idea for the construction of large space-reflector antennas. | Pengyuan Zhao Jinguo Liu Chenchen Wu Yangmin Li Keli Chen | 2020 | Chinese Journal of Mechanical Engineering2020，33，5： | 7 |
| 3 | High flux photocatalytic self-cleaning nanosheet C_(3)N_(4) membrane supported by cellulose nanofibers for dye wastewater purification显示文摘Hazardous dye substances discharged from the textile and dyestuff industries not only threaten local the surrounding ecosystems but are also hard to degraded.We report the preparation of process for a photocatalytic membrane device that can degrade dye pollution under visible light.This filtration membrane,with a well-organized multilayer structure,simultaneously achieves continuous and flow-through separation of degradation products.Cellulose nanofibers(CNFs)were used as a template for nanosheet C_(3)N_(4)(NS C_(3)N_(4))preparation;the performance for the photocatalytic degradation of dyes improved as the morphology changed from bulking to nanosheet.NS C3N4 was then attached to the surface of a prepared CNF membrane via vacuum filtration.This device exhibited high efficiency(the degradation rates of both Rhodamine B and Methylene blue both reached 96%),high flux(above 160 L·h^(-1)·m^(-2)·bar^(-1))and excellent stability(maintaining steady flux and high separation were maintained after 4 h).This easy-preparation,easy-scale-up,and low-cost process provides a new method of fabricating photocatalytic membrane devices for dye wastewater treatment. | Lilong Zhang Ge Meng Guifang Fan Keli Chen Yulong Wu Jian Liu | 2021 | Nano Research2021，14，8： | 3 |
| 4 | Progress in octahedral spherical hohlraum study显示文摘In this paper,we give a review of our theoretical and experimental progress in octahedral spherical hohlraum study.From our theoretical study,the octahedral spherical hohlraums with 6 Laser Entrance Holes(LEHs)of octahedral symmetry have robust high symmetry during the capsule implosion at hohlraum-to-capsule radius ratio larger than 3.7.In addition,the octahedral spherical hohlraums also have potential superiority on low backscattering without supplementary technology.We studied the laser arrangement and constraints of the octahedral spherical hohlraums,and gave a design on the laser arrangement for ignition octahedral hohlraums.As a result,the injection angle of laser beams of 50°-60°was proposed as the optimum candidate range for the octahedral spherical hohlraums.We proposed a novel octahedral spherical hohlraum with cylindrical LEHs and LEH shields,in order to increase the laser coupling efficiency and improve the capsule symmetry and to mitigate the influence of the wall blowoff on laser transport.We studied on the sensitivity of the octahedral spherical hohlraums to random errors and compared the sensitivity among the octahedral spherical hohlraums,the rugby hohlraums and the cylindrical hohlraums,and the results show that the octahedral spherical hohlraums are robust to these random errors while the cylindrical hohlraums are the most sensitive.Up till to now,we have carried out three experiments on the spherical hohlraum with 2 LEHs on Shenguang(SG)laser facilities,including demonstration of improving laser transport by using the cylindrical LEHs in the spherical hohlraums,spherical hohlraum energetics on the SGIII prototype laser facility,and comparisons of laser plasma instabilities between the spherical hohlraums and the cylindrical hohlraums on the SGIII laser facility. | Ke Lan Jie Liu Zhichao Li Xufei Xie Wenyi Huo Yaohua Chen Guoli Ren Chunyang Zheng Dong Yang Sanwei Li Zhiwen Yang Liang Guo Shu Li Mingyu Zhang Xiaoying Han Chuanlei Zhai Lifei Hou Yukun Li Keli Deng Zheng Yuan Xiayu Zhan Feng Wang Guanghui Yuan Haijun Zhang Bobin Jiang Lizhen Huang Wei Zhang Kai Du Runchang Zhao Ping Li Wei Wang Jingqin Su Xuewei Deng Dongxia Hu Wei Zhou Huaiting Jia Yongkun Ding Wanguo Zheng Xiantu He | 2016 | Matter and Radiation at Extremes2016，1，1： | 2 |
| 5 | Multiple amino acid substitutions are involved in the adaptation of H9N2 avian influenza virus to mice显示文摘 | Rui Wu Hongbo Zhang Keli Yang Wangwang Liang Zhongliang Xiong Zewen Liu Xuehai Yang Huabin Shao Xinmin Zheng Mingxin Chen Diping Xu | 2009 | Veterinary Microbiology2009，，1： | 1 |
| 6 | BISC:A bitmap itemset support counting approach for efficient frequent itemset mining显示文摘 | CHEN Jinlin XIAO Keli | | 0，，03： | 1 |
| 7 | Impact of antitumor regimens on the outcomes of cancer patients with COVID-19:a pooled analysis显示文摘Since the outbreak of coronavirus disease 2019(COVID-19),which is caused by the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)discovered in December 2019,the disease has emerged as a global pandemic(Shi et al.,2020;World Health Organization,2020).Several studies have shown a higher incidence of COVID-19,as well as related poor outcomes in patients with malignancies as compared with those without them(Liang et al.,2020;Tian et al.,2020). | Haohua LU Yu SHI Kelie CHEN Zhi CHEN Haihong ZHU Yuequn NIU Dajing XIA Yihua WU | 2021 | Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)2021，22，10： | 1 |
| 8 | Alkali-oxygen pulping of rice-straw: Two-stage pulping by alkali soaking and oxygen cooking显示文摘 | Chen Keli Kunio Tosaka Jisuke Hagashi | 1994 | TAPPI1994，77，7： | 1 |
| 9 | Effectiveness of erosion control measures along the Qinghai-Tibet highway, Tibetan plateau, China显示文摘 | Xianli Xu Keli Zhang Yaping Kong Jiding Chen Bofu Yu | 2006 | Transportation Research Part D2006，，11： | 1 |
| 10 | Identification of trace element sources and associated risk assessment in vegetable soils of the urban–rural transitional area of Hangzhou, China显示文摘 | Tao Chen Xingmei Liu Muzhi Zhu Keli Zhao Jianjun Wu Jianming Xu Panming Huang | 2007 | Environmental Pollution2007，，1： | 1 |
| 11 | Vector correlation in the H+D2 reaction and its isotopic variants:isotope effect on stereodynamics显示文摘 | Chen Maodu Han Keli Lou Nanquan | 2002 | Chem Phys Lett2002，357，56： | 1 |
| 12 | Theoretical studies of product polarization and state distributions of the H+HCl reaction显示文摘 | Chen Maodu Han Keli Lou Nanquan | 2002 | Chem Phys2002，283，3： | 1 |
| 13 | Alkali-oxygen pulping of rice-straw:two-stage pulping by alkali soaking and oxygen cooking显示文摘 | Chen Keli Kunio Tosaka Jisuke Hagashi | 1994 | TAPPI1994，77，7： | 1 |
| 14 | Temporal-spatial variability of desertification in an agro-pastoral transitional zone of northern Shaanxi Province, China显示文摘 | Yanbing Qi Qingrui Chang Keli Jia Mengyun Liu Jing Liu Tao Chen | 2011 | Catena2011，，1： | 1 |
| 15 | Antioxidant activities of extracts from five anti- vrial medicinal plants 显示文摘 | Keli Chen Geoft W Plumb Yongping Bao | 2005 | Journal of Enthropharmacology2005，96，20： | 1 |
| 16 | ACOUSTICAL PROPERTIES OF QING显示文摘The qing was an important percussion musical instrument in ancient China.Qing is a stone plate withspecial form.The vibration of qing is studied both theoretically and experimentally in this paper.Thevibrational modes of a qing have been calculated by using finite element method in accordance with the ex-perimental results.As compared with a rectangular plate,the frequency relations between the overtones arevaried with the changes of shape of the qing.From the analysis,it is possible to speculate upon the idea ofdesign of the qing in ancient time.In order to confirm the idea,the sound of qing has been simulated bycomputer and judged subjectively.An empirical formula for the calculation of the pitch frequency of qingsound is given. | CHEN Tong(Institute of Acoustics Academa Sinica)WANG Zhongyan(Keli High Technology Corporation) | 1989 | Chinese Journal of Acoustics1989，8，4： | 1 |
| 17 | High performance streaked X-ray spectrometer for research of laser-produced plasmas显示文摘In order to mitigate the effect of the strong electromagnetic pulse, which produces laser-plasma interactions, we designed a new streaked X-ray spectrometer (SXS) enclosed within a well-sealed, electromag- netic interference-free cavity. The SXS can cover a wide selection of spectral windows using interchangeable Bragg crystals and by appropriate adjustment of the Bragg angle. The SXS has been used to observe time-re- solved X-ray spectrum in the 2.5 keV to 3.5 keV photon-energy range, resulting in a demonstrated spectral res- olution of about 13 at 2960 eV with a time resolution of 10 ps. The observed time and spectral resolutions dem- onstrate the applicability of the SXS for studies of laser-produced plasmas. | Guo Luting Wei Minxi Hu Xin Deng Keli Chen Tao Deng Bo Zhang Lu Zhao Yang Li Jin Xiao Shaoqiu Liu Shenye | 2016 | 强激光与粒子束2016，28，2： | 0 |
| 18 | Global track extraction for probability hypothesis density filter显示文摘The probability hypothesis density(PHD), a well-known scheme for multi-target tracking in clutters, can obtain peaks of possible tracks, and its cluster-indexed method is widely accepted in further track extraction. However, the track extraction may face high risk in the case that the targets are so approached that it is hardly to discern their measurements. The concept of the distance between track sets in two adjacent times is defined and a consistency measure metric between any two peaks in two adjacent times is further proposed based on 'global information', containing spatial information(topology feature) among tracks, along with the temporal information of each track. Then, a global track extraction method is proposed based on the consistency belief and four decision rules. Via the simulation comparison with the cluster-indexed method, the proposed method can avoid the track break and mistake association. | Feng Yang Xi Shi Keli Liu Yan Liang Hao Chen | 2016 | Journal of Systems Engineering and Electronics2016，27，6： | 0 |
| 19 | MODERN AMERICAN ENGLISH显示文摘With China’s open door policy advocating that Chinese people study abroad, primarily in English-speaking countries, a text tailored to preparing these students is needed. Modern American English, (MAE) composed jointly by Chinese and American linguists, attempts to fill the void. The book’s introduction states a twofold purpose: to help Chinese students learn situational English and to introduce Western culture and society. By assessing MAE’s strength’s and weaknesses it is my intention to provide the publisher with some feedback that may be of some help for forthcoming revisions. | Chen Keli Chongqing University of Medical Sciences | 1994 | Chinese Journal of Applied Linguistics1994，18，0： | 0 |
| 20 | Biodegradable Plastics Show Huge Potential | Chen Qing and Liu Hong,Chengdu New Keli Chemical Science Co Ltd | 2010 | China Chemical Reporter2010，，24： | 0 |
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