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Nanopriming with selenium doped carbon dots improved rapeseed germination and seedling salt tolerance 被引量:1
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作者 Mohammad Nauman Khan Chengcheng Fu +7 位作者 xiaohui liu Yanhui Li Jiasen Yan Lin Yue Jiaqi Li Zaid Khan Lixiao Nie Honghong Wu 《The Crop Journal》 SCIE CSCD 2024年第5期1333-1343,共11页
Soil salinity is a big environmental issue affecting crop production.Although seed nanopriming has been widely used to improve seed germination and seedling growth under salinity,our knowledge about the underlying mec... Soil salinity is a big environmental issue affecting crop production.Although seed nanopriming has been widely used to improve seed germination and seedling growth under salinity,our knowledge about the underlying mechanisms is still insufficient.Herein,we newly synthesized selenium-doped carbon dots nanoparticles coated with poly acrylic acid(poly acrylic acid coated selenium doped carbon dots,PAA@Se-CDs)and used it to prime seeds of rapeseeds.The TEM(transmission electron microscope)size and zeta potential of PAA@Se-CDs are 3.8±0.2 nm and-30 mV,respectively.After 8 h priming,the PAA@Se-CDs nanoparticles were detected in the seed compartments(seed coat,cotyledon,and radicle),while no such signals were detected in the NNP(no nanoparticle control)group(SeO_2 was used as the NNP).Nanopriming with PAA@Se-CDs nanoparticles increased rapeseeds germination(20%)and seedling fresh weight(161%)under saline conditions compared to NNP control.PAA@Se-CDs nanopriming significantly enhanced endo-β-mannanase activities(255%increase,21.55μmol h^(-1)g^(-1)vs.6.06μmol h^(-1)g^(-1),at DAS 1(DAS,days after sowing)),total soluble sugar(33.63 mg g^(-1)FW(fresh weight)vs.20.23 mg g^(-1)FW)and protein contents(1.96μg g^(-1)FW vs.1.0μg g^(-1)FW)to support the growth of germinating seedlings of rapeseeds under salt stress,in comparison with NNP co ntrol.The respiration rate and ATP content were increased by 76%and 607%,respectively.The oxidative damage of salinity due to the overaccumulation of reactive oxygen species(ROS)was alleviated by PAA@Se-CDs nanopriming by increasing the antioxidant enzyme activities(SOD(superoxide dismutase),POD(peroxidase),and CAT(catalase)).Another mechanism behind PAA@Se-CDs nanopriming improving rapeseeds salt tolerance at seedling stage was reducing sodium(Na^(+))accumulation and improving potassium(K^(+))retention,hence increasing the K^(+)/Na^(+)ratio under saline conditions.Overall,our results not only showed that seed nanopriming with PAA@Se-CDs could be a good approach to improve salt tolerance,but also add more knowledge to the mechanism behind nanopriming-improved plant salt tolerance at germination and early seedling growth stage. 展开更多
关键词 PAA@Se-CDs Nanopriming Salt stress Antioxidant system K^(+)/Na^(+) balance ATP production
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Recent omics progress in nanobiotechnology for plant abiotic stress tolerance improvement 被引量:1
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作者 Lingling Chen Lan Zhu +7 位作者 xiaohui liu Lu Chen Han Zhou Huixin Ma Guilan Sun Ashadu Nyande Zhaohu Li Honghong Wu 《The Crop Journal》 SCIE CSCD 2024年第5期1274-1279,共6页
Use of nanomaterials(NMs)to improve plant abiotic stress tolerance(AST)is a hot topic in NM-enabled agriculture.Previous studies mainly focused on the physiological and biochemical responses of plants treated with NMs... Use of nanomaterials(NMs)to improve plant abiotic stress tolerance(AST)is a hot topic in NM-enabled agriculture.Previous studies mainly focused on the physiological and biochemical responses of plants treated with NMs under abiotic stress.To use NMs for improving plant AST,it is necessary to understand how they act on this tolerance at the omics and epigenetics levels.In this review,we summarized the knowledge of NM-improved abiotic stress tolerance in relation to omics(such as metabolic,transcriptomic,proteomic,and microRNA),DNA methylation,and histone modifications.Overall,NMs can improve plant abiotic stress tolerance through the modulation at omics and epigenetics levels. 展开更多
关键词 NANOMATERIALS OMICS Molecular mechanisms EPIGENETICS DNA methylation Histone modification
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Efficacy and safety of anlotinib combined with the STUPP regimen in patients with newly diagnosed glioblastoma: a multicenter, single-arm, phase Ⅱ trial
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作者 Shuzhen Lai Peijing Li +15 位作者 xiaohui liu Guihong liu Tieming Xie Xing Zhang Xiaoxuan Wang Jing Huang Yiqiang Tang Zhigang liu Guoping Shen Chaoming Li Fangxiao Lu Lei Wang Fagui Jiang Caixing Sun Yuanyuan Chen Ming Chen 《Cancer Biology & Medicine》 SCIE CAS CSCD 2024年第5期433-444,共12页
Objective:Glioblastomas are highly vascularized malignant tumors.We determined the efficacy and safety of the anti-angiogenic multi-kinase inhibitor,anlotinib,for a newly diagnosed glioblastoma.Methods:This multicente... Objective:Glioblastomas are highly vascularized malignant tumors.We determined the efficacy and safety of the anti-angiogenic multi-kinase inhibitor,anlotinib,for a newly diagnosed glioblastoma.Methods:This multicenter,single-arm trial(NCT04119674)enrolled 33 treatment-naïve patients with histologically proven glioblastomas between March 2019 and November 2020.Patients underwent treatment with the standard STUPP regimen[fractionated focal irradiation in daily fractions of 1.8-2 Gy given 5 d/w×6 w(total=54-60 Gy)]or radiotherapy plus continuous daily temozolomide(TMZ)(75 mg/m^(2)of body surface area/d,7 d/w from the first to the last day of radiotherapy),followed by 6 cycles of adjuvant TMZ(150-200 mg/m^(2)×5 d during each 28-d cycle)plus anlotinib(8 mg/d on d 1-14 of each 3-w cycle for 2 cycles during concomitant chemoradiotherapy,8 maximal cycles as adjuvant therapy,followed by maintenance at 8 mg/d.The primary endpoint was progression-free survival(PFS).Secondary endpoints included overall survival(OS)and adverse events(AEs).Results:Thirty-three patients received the planned treatment.The median PFS was 10.9 months(95%CI,9.9-18.7 months)and the 12-month PFS rate was 48.5%.The median OS was 17.4 months(95%CI,14.5-21.1 months)and the 12-month OS rate was 81.8%.The most common AEs included hypertriglyceridemia[58%(n=19)],hypoalbuminemia[46%(n=15)],and hypercholesterolemia[46%(n=15)]during concurrent chemoradiotherapy and leukopenia[73%(n=24)],hypertriglyceridemia[67%(n=22)],and neutropenia[52%(n=17)]during adjuvant therapy.Five patients discontinued treatment due to AEs.HEG1(HR,5.6;95%CI,1.3-23.7;P=0.021)and RP1L1 alterations(HR,11.1;95%CI,2.2-57.2;P=0.004)were associated with a significantly shorter PFS.Conclusions:Anlotinib plus the STUPP regimen has promising anti-tumor activity against glioblastoma and manageable toxicity.HEG1 and RP1L1 alterations might be novel predictive biomarkers of the response to anlotinib. 展开更多
关键词 GLIOBLASTOMA ANTI-ANGIOGENESIS multi-kinase inhibitor anlotinib TEMOZOLOMIDE progression-free survival
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The FRB-searching Pipeline of the Tianlai Cylinder Pathfinder Array
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作者 Zijie Yu Furen Deng +14 位作者 Shijie Sun Chenhui Niu Jixia Li Fengquan Wu Wei-Yang Wang Yougang Wang Shifan Zuo Lin Shu Jie Hao xiaohui liu Reza Ansari Ue-Li Pen Albert Stebbins Peter Timbie Xuelei Chen 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第8期113-132,共20页
This paper presents the design,calibration,and survey strategy of the Fast Radio Burst(FRB)digital backend and its real-time data processing pipeline employed in the Tianlai Cylinder Pathfinder Array.The array,consist... This paper presents the design,calibration,and survey strategy of the Fast Radio Burst(FRB)digital backend and its real-time data processing pipeline employed in the Tianlai Cylinder Pathfinder Array.The array,consisting of three parallel cylindrical reflectors and equipped with 96 dual-polarization feeds,is a radio interferometer array designed for conducting drift scans of the northern celestial semi-sphere.The FRB digital backend enables the formation of 96 digital beams,effectively covering an area of approximately 40 square degrees with the 3 dB beam.Our pipeline demonstrates the capability to conduct an automatic search of FRBs,detecting at quasi-realtime and classifying FRB candidates automatically.The current FRB searching pipeline has an overall recall rate of88%.During the commissioning phase,we successfully detected signals emitted by four well-known pulsars:PSR B0329+54,B2021+51,B0823+26,and B2020+28.We report the first discovery of an FRB by our array,designated as FRB 20220414A.We also investigate the optimal arrangement for the digitally formed beams to achieve maximum detection rate by numerical simulation. 展开更多
关键词 instrumentation interferometers-methods data analysis-(stars )pulsars general-telescopes
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Experiments and kinetic modeling of the sorbitol dehydration to isosorbide catalyzed by sulfuric acid under conditions of non-constant volume
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作者 Dechang Cheng Zhihong Ma +4 位作者 Ziyang liu xiaohui liu Tao liu Weizhen Sun Ling Zhao 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第9期281-289,共9页
Isosorbide is a novel bio-based material derived as a secondary dehydration product of sorbitol.This work focuses on the kinetics of sulfuric acid-catalyzed dehydration of sorbitol under conditions of nonconstant volu... Isosorbide is a novel bio-based material derived as a secondary dehydration product of sorbitol.This work focuses on the kinetics of sulfuric acid-catalyzed dehydration of sorbitol under conditions of nonconstant volume.Herein,the effects of stirring rate,catalyst dosage,reaction temperature,and reaction time on the dehydration reaction of sorbitol were investigated.The yield of isosorbide up to 77.13%was obtained after 1.5 h of reaction time under conditions of 2 kPa,1.0%(mass)catalyst dosage,and 413.15 K.Based on the sorbitol dehydration reaction mechanism and a simplified reaction network,a kinetic model was developed in this work.A good agreement was accomplished between kinetic modeling and experiments between 393.15 and 423.15 K.The fitting results indicate that side reactions with higher activation energies are more affected by reaction temperatures,and the main side reaction that influences the selectivity of isosorbide is the oligomerization reaction among the primary dehydration products of sorbitol.The model fitting of the catalyst amounts effect shows that the effective concentration of sulfuric acid would be reduced with the increase of dosage due to the molecular agglomeration effect.Hopefully,the kinetic experiments and modeling results obtained in this work will be helpful to the design and optimization of the industrial sorbitol dehydration process. 展开更多
关键词 ISOSORBIDE Sorbitol dehydration Non-constant volume Kinetic modeling
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On the Energy Budget of Starquake-induced Repeating Fast Radio Bursts
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作者 Wei-Yang Wang Chen Zhang +7 位作者 Enping Zhou xiaohui liu Jiarui Niu Zixuan Zhou He Gao Jifeng liu Renxin Xu Bing Zhang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第10期180-188,共9页
With a growing sample of fast radio bursts(FRBs),we investigate the energy budget of different power sources within the framework of magnetar starquake triggering mechanism.During a starquake,the energy can be release... With a growing sample of fast radio bursts(FRBs),we investigate the energy budget of different power sources within the framework of magnetar starquake triggering mechanism.During a starquake,the energy can be released in any form through strain,magnetic,rotational,and gravitational energies.The strain energy can be converted from three other kinds of energy during starquakes.The following findings are revealed:(1)The crust can store free magnetic energy of~10^(46)erg by existing toroidal fields,sustaining 10^(6)bursts with frequent starquakes occurring due to crustal instability.(2)The strain energy develops as a rigid object spins down,which can be released during a global starquake accompanied by a glitch.However,it takes a long time to accumulate enough strain energy via spindown.(3)The rotational energy of a magnetar with P■0.1 s can match the energy and luminosity budget of FRBs.(4)The budget of the total gravitational energy is high,but the mechanism and efficiency of converting this energy to radiation deserve further exploration. 展开更多
关键词 stars:magnetars stars:neutron radiation mechanisms:non-thermal
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Analysis of the Application and Effect of Homemade Medical Scrotal Support Shorts
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作者 Jianbin Cheng xiaohui liu Lin Lin 《Journal of Clinical and Nursing Research》 2024年第2期244-248,共5页
Objective:To design and manufacture medical scrotal support shorts for patients with enlarged scrotum and observe its application and effect.Methods:40 patients with enlarged scrotum admitted to the basic surgery depa... Objective:To design and manufacture medical scrotal support shorts for patients with enlarged scrotum and observe its application and effect.Methods:40 patients with enlarged scrotum admitted to the basic surgery department from February 2021 to March 2023 were selected and divided into a test group and a control group according to their time of admission,with the test group using scrotal support shorts and the control group using ordinary shorts without scrotal support pockets or diapers.Results:The complication rate of skin injury in the scrotum and the surrounding inguinal area of the patients in the test group was significantly lower than that of the control group(P<0.01).The medical cost covered by patients in the test group was significantly lower than that of the control group(P<0.01)and the hospitalization satisfaction of the patients in the test group was significantly higher than that of the control group(P<0.01).The difference in the therapeutic effect of the test groups was statistically significant when compared with the control group(P<0.05).Conclusion:Homemade medical scrotal support shorts reduced the local enlargement of the scrotum and bleeding,but also protected the scrotum and the surrounding skin to prevent secondary injuries.The process of patient care was simple and promoted their recovery.The length of hospitalization was also decreased,the burden of health care costs was reduced,and the overall comfort and satisfaction of the patient was improved. 展开更多
关键词 Enlarged scrotum Medical scrotal support shorts Nursing care
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大数据背景下智慧交通治理模式研究——以中国东莞为例
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作者 刘小慧 李海青 《工程设计与施工》 2020年第12期4-6,共3页
随着科学技术的不断发展和大数据技术的持续进步,智慧交通治理模式开始在当前各大城市进行推广,其应用有效提升了城市交通监管质量,减少了城市堵塞问题,提升了人们的交通体验。论文主要针对大数据背景下智慧交通治理模式在中国东莞的应... 随着科学技术的不断发展和大数据技术的持续进步,智慧交通治理模式开始在当前各大城市进行推广,其应用有效提升了城市交通监管质量,减少了城市堵塞问题,提升了人们的交通体验。论文主要针对大数据背景下智慧交通治理模式在中国东莞的应用进行探究,指出智慧交通治理模式的构建形式以及应用价值,希望能为中国交通行业的持续稳定发展提供一定的参考。 展开更多
关键词 大数据 智慧交通 治理模式
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泵供量和纺丝液浓度对Y形Lyocell纤维截面形状与性能的影响 被引量:1
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作者 沈洋 刘晓慧 +3 位作者 杨革生 张慧慧 于敏敏 邵惠丽 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2020年第10期135-140,共6页
采用Y形截面喷丝孔,通过干喷湿纺制备异形Lyocell纤维,通过扫描电子显微镜、光学显微镜和纤维强伸度仪分别研究了泵供量和纺丝液浓度对纤维截面形状、异形度及力学性能的影响。研究结果表明,尽管采用的喷丝孔截面为Y形,但由于孔口胀大效... 采用Y形截面喷丝孔,通过干喷湿纺制备异形Lyocell纤维,通过扫描电子显微镜、光学显微镜和纤维强伸度仪分别研究了泵供量和纺丝液浓度对纤维截面形状、异形度及力学性能的影响。研究结果表明,尽管采用的喷丝孔截面为Y形,但由于孔口胀大效应,所得Lyocell纤维截面类似三角形。随着泵供量增加,纤维的异形度略有减小,力学性能则先上升后趋于平稳,当泵供量为16 g/min时,可制备出具有较高异形度且断裂强度最高的类三角形Lyocell纤维。随着纺丝液浓度的增大,纤维截面形状更加趋于喷丝孔形状,异形度逐渐提高,同时纤维力学性能也逐渐提高,其中纺丝液浓度为13%时制得的Y形Lyocell纤维的截面形状与力学性能最佳。 展开更多
关键词 LYOCELL纤维 异形纤维 截面形状 力学性能 异形度
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Fe的原位掺杂对Pt/Silicalite-1催化丙烷脱氢反应性能的提升作用 被引量:1
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作者 沈姗姗 刘晓晖 +1 位作者 郭勇 王艳芹 《物理化学学报》 SCIE CAS CSCD 北大核心 2023年第7期79-88,共10页
利用一步水热法制备了原位掺杂Fe的Silicalite-1分子筛载体,浸渍得到相应的Pt基催化剂,用于丙烷的直接脱氢反应。作为对比,也制备了Pt/Silicalite-1和共浸渍的Pt1Fe2/Silicalite-1催化剂。研究发现较之Pt/Silicalite-1催化剂,原位掺入Fe... 利用一步水热法制备了原位掺杂Fe的Silicalite-1分子筛载体,浸渍得到相应的Pt基催化剂,用于丙烷的直接脱氢反应。作为对比,也制备了Pt/Silicalite-1和共浸渍的Pt1Fe2/Silicalite-1催化剂。研究发现较之Pt/Silicalite-1催化剂,原位掺入Fe的Pt/Fe-Silicalite-1催化剂反应性能有了很大程度地提高,而共浸渍制备的Pt1Fe2/Silicalite-1催化剂反应性能有所降低。在Pt/Fe-Silicalite-1催化剂上,尽管丙烷的初始转化率略有降低,但丙烯的选择性和催化稳定性大幅提高。反应8h后丙烷转化率稳定在43.7%、丙烯选择性达到98.0%;且在80h内基本保持不变。深入表征发现Fe的原位掺入使得Pt物种配位饱和度提高,避免了丙烷的深度脱氢使得丙烯选择性提高、结焦速率降低;且通过Fe-Pt之间电子转移,使得Pt上的电子云密度增强,增强了丙烯的脱附能力,进一步降低了结焦速率。另外载体中的Fe位点可以锚定Pt,使得Pt物种不易聚集,从而进一步提高了Pt/Fe-Silicalite-1的稳定性,使得该催化剂在反应80 h后仍保持高转化率和选择性。 展开更多
关键词 丙烷脱氢 SILICALITE-1 Pt基催化剂 Fe原位掺杂
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Co@CoO催化剂表面类氢负物种NH_(2)^(δ-)驱动下的还原胺化反应
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作者 郭万君 王志强 +5 位作者 相爽 景亚轩 刘晓晖 郭勇 龚学庆 王艳芹 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2023年第4期181-190,共10页
胺类化合物作为一类重要的精细化学品,广泛应用于合成染料、表面活性剂、聚合物、药品和农用化学品.催化还原胺化是合成胺类化合物的重要手段.在还原胺化反应中,水是唯一的副产物,且反应条件温和,符合绿色化学原则,因此受到了广泛关注.... 胺类化合物作为一类重要的精细化学品,广泛应用于合成染料、表面活性剂、聚合物、药品和农用化学品.催化还原胺化是合成胺类化合物的重要手段.在还原胺化反应中,水是唯一的副产物,且反应条件温和,符合绿色化学原则,因此受到了广泛关注.在过去的几十年里,生物质衍生的羰基化合物(糠醛、环戊酮、5-羟甲基糠醛等)的催化还原胺化得到了特别关注,为利用可再生资源可持续地生产胺类提供了可能性.通常,金属(Ru,Ir,Pt,Rh,Co,Ni等)被认为是还原胺化的活性中心,相关研究快速发展,但大部分研究都围绕着金属负载型催化剂展开,对于以金属氧化物为活性中心鲜有研究.另外,还原胺化过程研究表明,席夫碱在反应开始阶段迅速生成,然后通过氨解产生相应的伯胺;但席夫碱氨解为伯胺的过程速率较慢,是该反应的决速步骤,因此设计高效催化剂加快席夫碱的氨解是还原胺化过程中的重要科学问题.受孤立的路易斯酸碱对可以催化氢气异裂过程的启发,本文利用具有核壳结构的Co@Co O为催化剂,发现表面具有氧空位的CoO具有独特的解离NH_(3)生成类氢负物种(NH_(2)^(δ-))的能力,该NH_(2)^(δ-)物种能够加速席夫碱的氨解,从而使得该催化剂展现出较好的还原胺化性能,且具有较好的稳定性,在环戊酮胺化为环戊胺过程中使用10次没有失活.通过密度泛函理论(DFT)计算和D_(2)同位素示踪实验发现了类氢负物种NH_(2)^(δ-),且验证了H^(δ-)和NH_(2)^(δ-)物种在Co O表面可稳定地共吸附,席夫碱在催化剂表面吸附较弱,使得希夫碱中间体可以在解离NH_(2)^(δ-)和H^(δ-)后的CoO表面自由移动,从而与表面解离的H^(-)和NH_(2)^(δ)–发生分子碰撞,生成伯胺,最后脱附完成催化循环.本文实现了金属氧化物催化还原胺化反应.更重要的是,在加氢/氢解反应中,孤立的路易斯酸碱对上异裂产生的H^(δ-)物种虽然具有较好的活性,但是没有H^(δ-)物种参与反应直接证据的相关报道,本研究发现的类氢负物种NH_(2)^(δ-)参与胺化反应的证据间接表明了H^(δ-)物种参与加氢/氢解反应的可能性. 展开更多
关键词 还原胺化 类氢负物种NH_(2)^(δ-) Co@CoO 席夫碱
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High-yield production of 2,5-dimethylfuran from 5-hydroxymethylfurfural over carbon supported Ni–Co bimetallic catalyst 被引量:7
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作者 Panpan Yang Qineng Xia +1 位作者 xiaohui liu Yanqin Wang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2016年第6期1015-1020,共6页
The catalytic conversion of 5-hydroxymethylfurfural (HMF) to 2,5-dimethylfuran (DMF) has attracted extensive research interests because DMF can be used as potential and competitive renewable transportation fuel or add... The catalytic conversion of 5-hydroxymethylfurfural (HMF) to 2,5-dimethylfuran (DMF) has attracted extensive research interests because DMF can be used as potential and competitive renewable transportation fuel or additives. Here we report a non-noble bimetallic catalyst with improved activity for hydrogenation and hydrogenolysis by introducing active carbon as support into a nickel–cobalt catalyst. The characterizations of the catalyst indicate that the Ni and Co species are uniformly dispersed on the active carbon through the wetness impregnation method. The influences of reaction temperature and hydrogen pressure are systematically investigated and an excellent yield (up to 95%) of DMF can be obtained at relatively mild conditions, 130 °C and 1 MPa H2, over the carbon supported Ni–Co bimetallic catalyst. The high catalytic activity originates from the synergistic effect between Ni and CoOxspecies, the high BET surface area of the catalyst, and the uniform dispersion of Ni and Co species on the active carbon. The catalyst could be reused for 5 times without loss of activity in a batch reactor. Futhermore, the conversion of HMF to DMF on a fixed-bed reactor was also investigated and the 2%Ni–20%Co/C catalyst exhibited an excellent yield to DMF (>90%) for 71 h time on stream, indicating the high activity and stability of the catalyst. © 2016 Science Press 展开更多
关键词 Batch reactors BIOMASS CATALYSTS Chemical reactors Cobalt compounds Fuel additives HYDROGENOLYSIS HYDROLYSIS NICKEL
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Depolymerization and hydrodeoxygenation of lignin to aromatic hydrocarbons with a Ru catalyst on a variety of Nb-based supports 被引量:8
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作者 Di Ma Shenglu Lu +2 位作者 xiaohui liu Yong Guo Yanqin Wang 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2019年第4期609-617,M0006,共10页
Efficient conversion of lignin to aromatic hydrocarbons via depolymerization and subsequent hydrodeoxygenation is important.Previously,we found that NbOx species played a key role in the activation and cleavage of C-O... Efficient conversion of lignin to aromatic hydrocarbons via depolymerization and subsequent hydrodeoxygenation is important.Previously,we found that NbOx species played a key role in the activation and cleavage of C-O bonds in lignin and its model compounds.In this study,commercial niobic acid(HY-340),niobium phosphate(NbPO-CBMM)and lab-made layered niobium oxide(Nb2O5-Layer)were chosen as supports to study the effect of Brosted and Lewis acids on the activation of C-O bonds in lignin conversion.A variety of Ru-loaded,Nb-based catalysts with different Ru particle sizes were prepared and applied to the conversion of p-cresol.The results show that all the Ru/Nb-based catalysts produce high mole yields of C7-C9 hydrocarbons(82.3%-9.1%).What's more,Ru/Nb2O5-Layer affords the best mole yield of C7-C9 hydrocarbons and selectivity for C7-C9 aromatic hydrocarbons,of up to 99.1% and 88.0%,respectively.Moreover,it was found that Lewis acid sites play important roles in the depolymerization of enzymatic lignin into phenolic monomers and the cleavage of the C-O bond of phenols.Additionally,the electronic state and particle size of Ru are significant factors which influence the selectivity for aromatic hydrocarbons.A partial positive charge on the metallic Ru surface and a smaller Ru particle size are beneficial in improving the selectivity for aromatic hydrocarbons. 展开更多
关键词 LIGNIN Aromatic hydrocarbons Nb-based supports Lewis acid sites Ru
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Set-Membership Filtering Subject to Impulsive Measurement Outliers:A Recursive Algorithm 被引量:6
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作者 Lei Zou Zidong Wang +1 位作者 Hang Geng xiaohui liu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2021年第2期377-388,共12页
This paper is concerned with the set-membership filtering problem for a class of linear time-varying systems with norm-bounded noises and impulsive measurement outliers.A new representation is proposed to model the me... This paper is concerned with the set-membership filtering problem for a class of linear time-varying systems with norm-bounded noises and impulsive measurement outliers.A new representation is proposed to model the measurement outlier by an impulsive signal whose minimum interval length(i.e.,the minimum duration between two adjacent impulsive signals)and minimum norm(i.e.,the minimum of the norms of all impulsive signals)are larger than certain thresholds that are adjustable according to engineering practice.In order to guarantee satisfactory filtering performance,a so-called parameter-dependent set-membership filter is put forward that is capable of generating a time-varying ellipsoidal region containing the true system state.First,a novel outlier detection strategy is developed,based on a dedicatedly constructed input-output model,to examine whether the received measurement is corrupted by an outlier.Then,through the outcome of the outlier detection,the gain matrix of the desired filter and the corresponding ellipsoidal region are calculated by solving two recursive difference equations.Furthermore,the ultimate boundedness issue on the time-varying ellipsoidal region is thoroughly investigated.Finally,a simulation example is provided to demonstrate the effectiveness of our proposed parameter-dependent set-membership filtering strategy. 展开更多
关键词 Boundedness analysis impulsive measurement outliers parameter-dependent filter set-membership filtering time-varying systems
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An Overview of Recommendation Techniques and Their Applications in Healthcare 被引量:5
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作者 Wenbin Yue Zidong Wang +1 位作者 Jieyu Zhang xiaohui liu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2021年第4期701-717,共17页
With the increasing amount of information on the internet,recommendation system(RS)has been utilized in a variety of fields as an efficient tool to overcome information overload.In recent years,the application of RS f... With the increasing amount of information on the internet,recommendation system(RS)has been utilized in a variety of fields as an efficient tool to overcome information overload.In recent years,the application of RS for health has become a growing research topic due to its tremendous advantages in providing appropriate recommendations and helping people make the right decisions relating to their health.This paper aims at presenting a comprehensive review of typical recommendation techniques and their applications in the field of healthcare.More concretely,an overview is provided on three famous recommendation techniques,namely,content-based,collaborative filtering(CF)-based,and hybrid methods.Next,we provide a snapshot of five application scenarios about health RS,which are dietary recommendation,lifestyle recommendation,training recommendation,decision-making for patients and physicians,and disease-related prediction.Finally,some key challenges are given with clear justifications to this new and booming field. 展开更多
关键词 Collaborative filtering(CF) content-based recommendation healthcare recommendation system(RS)
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Highly efficient Nb2O5 catalyst for aldol condensation of biomass-derived carbonyl molecules to fuel precursors 被引量:3
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作者 Yaxuan Jing Yu Xin +2 位作者 Yong Guo xiaohui liu Yanqin Wang 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2019年第8期1168-1177,共10页
Aldol condensation is of significant importance for the production of fuel precursors from biomass- derived chemicals and has received increasing attention. Here we report a Nb2O5 catalyst with excellent activity and ... Aldol condensation is of significant importance for the production of fuel precursors from biomass- derived chemicals and has received increasing attention. Here we report a Nb2O5 catalyst with excellent activity and stability in the aldol condensation of biomass-derived carbonyl molecules. It is found that in the aldol condensation of furfural with 4-heptanone, Nb2O5 has obviously superior activity, which is not only better than that of other common solid acid catalysts (ZrO2 and Al2O3), more importantly, but also better than that of solid base catalysts (MgO, CaO, and magnesium- aluminum hydrotalcite). The detailed characterizations by N2 sorption/desorption, NH3-TPD, Py-FTIR and DRIFTS study of acetone adsorption reveal that Nb2O5 has a strong ability to activate the C=O bond in carbonyl molecules, which helps to generate a metal enolate intermediate and undergo the nucleophilic addition to form a new C–C bond. Furthermore, the applicability of Nb2O5 to aldol condensation is extended to other biomass-derived carbonyl molecules and high yields of target fuel precursors are obtained. Finally, a multifunctional Pd/Nb2O5 catalyst is prepared and successfully used in the one-pot synthesis of liquid alkanes from biomass-derived carbonyl molecules by combining the aldol condensation with the sequential hydrodeoxygenation. 展开更多
关键词 Aldol condensation NB2O5 C=O activation Fuel precursor Bio-liquid alkane One-pot process
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Low-cost synthesis of nanoaggregate SAPO-34 and its application in the catalytic alcoholysis of furfuryl alcohol 被引量:3
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作者 Qianqian Guo Fan Yang +3 位作者 xiaohui liu Mengqing Sun Yong Guo Yanqin Wang 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2020年第11期1772-1781,共10页
Silicoaluminophosphate-34(SAPO-34) molecular sieves have important applications in the petrochemical industry as a result of their shape selectivity and suitable acidity. In this work, nanoaggregate SAPO-34 with a lar... Silicoaluminophosphate-34(SAPO-34) molecular sieves have important applications in the petrochemical industry as a result of their shape selectivity and suitable acidity. In this work, nanoaggregate SAPO-34 with a large external surface area was obtained by dissolving pseudoboehmite and tetraethylorthosilicate in an aqueous solution of tetraethylammonium hydroxide and subsequently adding phosphoric acid. After hydrolysis in an alkaline solution, the aluminum and silicon precursors exist as Al(OH)4-and SiO2(OH)-, respectively;this is beneficial for rapid nucleation and the formation of nanoaggregates in the following crystallization process. Additionally, to study the effect of the external surface area and pore size on the catalytic performance of different SAPO-34 structures, the alcoholysis of furfuryl alcohol to ethyl levulinate(EL) was chosen as a model reaction. In a comparison with the traditional cube-like SAPO-34, nanoaggregate SAPO-34 generated a higher yield of 74.1% of EL, whereas that with cube-like SAPO-34 was only 19.9%. Moreover, the stability was remarkably enhanced for nanoaggregate SAPO-34. The greater external surface area and larger number of external surface acid sites are helpful in improving the catalytic performance and avoiding coke deposition. 展开更多
关键词 Nanoaggregate SPAO-34 External surface area Low cost Catalytic alcoholysis Furfuryl alcohol
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Co@CoO:An efficient catalyst for the depolymerization and upgrading of lignocellulose to alkylcyclohexanols with cellulose intact 被引量:1
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作者 Shuang Xiang Lin Dong +5 位作者 Zhiqiang Wang Xue Han Yong Guo xiaohui liu Xue-Qing Gong Yanqin Wang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第2期191-199,I0006,共10页
The depolymerization and upgrading of lignin from raw biomass,while keeping cellulose intact is important in biorefinery and various metal-based catalysts have been used in reductive catalytic fractionation,a key meth... The depolymerization and upgrading of lignin from raw biomass,while keeping cellulose intact is important in biorefinery and various metal-based catalysts have been used in reductive catalytic fractionation,a key method in"lignin-first"strategy,Recently,we found that a core-shell structured Co@CoO catalyst with CoO shell as the real active site had excellent performance in the hydrogenolysis of 5-hydromethylfurfural to 2,5-dimethylfuran due to its unique ability to dissociate H_(2)and yield active H^(δ-)species(Xiang et al.,2022).In this work,we report a one-pot depolymerization and upgrading of lignocellulose to alkylcyclohexanols,a flavour precursor,with intact cellulose over this unique core-shell structured catalyst,Co@CoO.Lignin model compounds(β-O-4,4-O-5,α-O-4)were first used to clarify the activity of Co@CoO catalyst.Then,the one-pot conversion of various organosolv lignin(birch,pine and poplar)to alkylcyclohexanols was realized with the mass yield of alkylcyclohexanols up to25.8 wt%from birch lignin under the reaction condition of 210℃,1 MPa H_(2),16 h.Finally,the corresponding woody sawdusts were used as feedstocks and found that the Co@CoO catalyst indeed preferentially depolymerized and upgraded the lignin part and obtained the same alkylcyclohexanols products with the retention of cellulose-rich pulp.The collected alkylcyclohexanols were further esterified to obtain valueadded esters,which can be used as flavors.This work will inspire the design of new efficient metal oxide catalysts in lignin fractionation and depolymerization to high-value-added chemicals with intact cellulose. 展开更多
关键词 LIGNOCELLULOSE LIGNIN DEPOLYMERIZATION Co@CoO Alkylcyclohexanols
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The Temporal Relation between Cardiomyopathy and LBBB and Response to Cardiac Resynchronization Therapy:Case Series and Literature Review 被引量:1
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作者 Sanshuai Chang Yi He +8 位作者 Hui Wang Fei Guo Qiang Lv Junping Kang Rong Bai xiaohui liu Xin Du Changsheng Ma Jianzeng Dong 《Cardiovascular Innovations and Applications》 2020年第1期163-172,共10页
Background:Left bundle branch block(LBBB)-induced cardiomyopathy has been proposed,but the association between LBBB and cardiac resynchronization therapy(CRT)response remains unclear and practical criteria for selecti... Background:Left bundle branch block(LBBB)-induced cardiomyopathy has been proposed,but the association between LBBB and cardiac resynchronization therapy(CRT)response remains unclear and practical criteria for selecting CRT candidates are needed.Methods:One hundred and seventeen consecutive heart failure patients were reviewed,24 of whom received CRT.Only two patients had a clear temporal relation between cardiomyopathy and LBBB.Results:Compared with the patient with“cardiomyopathy-induced LBBB,”the patient with“LBBB-induced cardiomyopathy”had higher left ventricular(LV)wall thickness,higher LV wall thickening rate,higher peak circumferential strain,and longer peak circumferential strain delay.The LV deformation patterns in the two patients were obviously distinct on cardiovascular magnetic resonance tissue tracking.During follow-up,the patient with LBBB-induced cardiomyopathy had a good response to CRT(LV ejection fraction 23 before CRT vs.30%at 6 months vs.29 at 12 months vs.32%at 18 months;LV end-diastolic diameter 77 mm before CRT vs.66 mm at 6 months vs.62 mm at 12 months vs.63 mm at 18 months),and the other patient had no response to CRT(LV ejection fraction 29 before CRT vs.29%at 6 months vs.26 at 12 months vs.22%at 24 months;LV end-diastolic diameter 85 mm before CRT vs.88 mm at 6 months vs.85 mm at 12 months vs.84 mm at 24 months).Conclusion:The temporal relation between cardiomyopathy and LBBB could be a determinant for CRT response.Cardiovascular magnetic resonance tissue tracking may be a useful tool to identify the chronological order and a principal consideration for selecting candidates for CRT.Larger prospective clinical trials are needed to study the prevalence of,time course of,and risk factors for LBBB-induced cardiomyopathy. 展开更多
关键词 LEFT BUNDLE branch block CARDIOMYOPATHY heart failure CARDIOVASCULAR magnetic resonance cardiac RESYNCHRONIZATION therapy
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Construction of Oryza sativa genome contigs by fingerprint strategy 被引量:1
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作者 TAO QUANZHOU YUEMIN QIAN +7 位作者 HAIYING ZHAO SHULIANG YU LONGFANG QIU BOQIAN WU JIA ZHU DI YU xiaohui liu GUOFAN HONG(National Center for Gene Research, Chinese Academy of Sciences, Shanghai 200233, China.)(Shanghai Institute of Biochemistry, Chinese Acad 《Cell Research》 SCIE CAS CSCD 1995年第2期263-271,共9页
We described the construction of BAC contigs of the genome of a indica variety of Oryza sativa, Guang Lu Ai 4.An entire representative (sixfold coverage of rice chromosomes) and genetically stable BAC library of rice ... We described the construction of BAC contigs of the genome of a indica variety of Oryza sativa, Guang Lu Ai 4.An entire representative (sixfold coverage of rice chromosomes) and genetically stable BAC library of rice genome constructed in this lab has been systematically analysed by restriction enzyme fragmentation and polyacrylamide gel electrophoresis. And all the images thus obtained were subject to image-processing, which consisted of preliminary location of bands, cooperative tracking of lanesby correlation of adjacent bands, a precise densitometric pass, alignment at the marker bands with the standard,optional interactive editing, and normalization of the accepted bands. The contigs were generated based on the Computer Software specially designed for genome map ping. The number of contigs with 600 kb in length on average was 464; of contigs with 1000 kb in length on average was 107; of contigs with 1500 kb in length on average was 23. Therefore, all the contigs we have obtained amounted up to 420 megabases in length. Considering the size of rice genome (430 megabased), the contigs generated in this lab have covered nearly 98% of the rice genome. We are now in the process of mapping the contigs to chromosomes. 展开更多
关键词 CONTIG GENOME INDICA oryza sativa BAC
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