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大学生心理健康教育课程建设的困境及突破 被引量:39
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作者 李忠艳 雒文虎 胡菊华 《黑龙江高教研究》 北大核心 2021年第12期145-149,共5页
文章深入解读大学生心理健康教育课程建设的诸多影响机理,从宏观的急速社会变革对个体心理造成强烈冲击和网络文化的心理扰动到课程本身的多质性特征要求,再到教育对象——大学生心理发展状态的滞后性表现,多角度分析课程建设的现实困... 文章深入解读大学生心理健康教育课程建设的诸多影响机理,从宏观的急速社会变革对个体心理造成强烈冲击和网络文化的心理扰动到课程本身的多质性特征要求,再到教育对象——大学生心理发展状态的滞后性表现,多角度分析课程建设的现实困境。以建立并发展大学生心理健康教育学科为突破口,从建立并完善课程体系入手,优化网络化课程模式,建立并落实师资队伍建设规划,积极推进大学生心理健康教育课程建设的高效有序发展。 展开更多
关键词 大学生 心理健康教育课程 多质化
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SOX2/DRD2 signaling pathway facilitates astrocytic dedifferentiation in cerebral ischemic mice
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作者 YI Xuyang KANG Enming +4 位作者 WANG Yanjin ZHANG Kun LIN Wei WU Shengxi WANG Yazhou 《神经解剖学杂志》 CAS CSCD 北大核心 2024年第3期277-286,共10页
Objective:To explore the effects of dopamine receptor D2(DRD2)on astrocytic dedifferentiation based on SOX2-regulated genes in neural stem cells(NSCs)and astrocytes.Methods:Immunofluorescence staining and SOX2-GFP mic... Objective:To explore the effects of dopamine receptor D2(DRD2)on astrocytic dedifferentiation based on SOX2-regulated genes in neural stem cells(NSCs)and astrocytes.Methods:Immunofluorescence staining and SOX2-GFP mice were used to examine the lineage differentiation of SOX2-positive cells during the development of cerebral cortex.Primary NSCs/astrocytes culture,ChIP-seq and Western Blot were adopted to analyze and verify the expression of candidate genes.Pharmacological manipulation,neurosphere formation,photochemical ischemia,immunofluorescence staining and behavior tests were adopted to evaluate the effects of activating DRD2 signaling on astrocytic dedifferentiation.Results:Immunofluorescence staining demonstrated the NSC-astrocyte switch of SOX2-expression in the normal development of cerebral cortex.ChIP-seq revealed enrichment of DRD2 signaling by SOX2-bound enhancers in NSCs and SOX2-bound promoters in astrocytes.Western Blot and immunofluorescence staining verified the expression of DRD2 in NSCs and reactive astrocytes.Application of quinagolide hydrocholoride(QH),an agonist of DRD2,significantly promoted astrocytic dedifferentiation both in vitro and in vivo following ischemia.In addition,quinagolide hydrocholoride treatment improved locomotion recovery.Conclusion:Activating DRD2 signaling facilitates astrocytic dedifferentiation and may be used to treat ischemic stroke. 展开更多
关键词 cerebral ischemia ASTROCYTE DEDIFFERENTIATION SOX2 dopamine D2 receptor(DRD2) mouse
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Anti-oxidation Activity in Vitro of Polysaccharides of Dendrobium Huoshanense and Dendrobium moniliforme 被引量:30
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作者 汪曙 魏凤娟 +1 位作者 蔡永萍 林毅 《Agricultural Science & Technology》 CAS 2009年第6期121-124,共4页
[ Objective ] The aim was to study the effects of polysaccharides of Dendrobium Huoshanense and Dendrobium moniliforme on oxygen free radicals and lipid peroxidation in vitro. [ Method] The scavenging action on .OH of... [ Objective ] The aim was to study the effects of polysaccharides of Dendrobium Huoshanense and Dendrobium moniliforme on oxygen free radicals and lipid peroxidation in vitro. [ Method] The scavenging action on .OH of polysaccharides, the inhibition action on O2^- of polysaccharides, MDA production of lipid peroxidation were measured by Fenton reaction, self oxidation system of C6H3( OH)3 and TBA method respectively. [ Result] The half scavenging concentration on ·OH of potysaccharides of Dendrobium Huoshanense and Dendrobium moniliforme was 6.79 and 6.75 mg/ml respectively. As to their half inhibition concentration on O2 , the data was 3, 04 and 3.44 mg/ml respectively. Two kinds of Dendrobium polysaccharides bothhad inhibitory actions on lipid peroxidation of liver homogenate induced by auto-oxidation and inducedoxidation, and they could alleviate oxidation damages of mice liver mitochondria induced by Vc-Fe2+ system. [Conclusion] Two kinds of Dendrobium polysacchaddes both had remarkable anti-oxidation activity in vitro. 展开更多
关键词 Dendrobium Huoshanense Dendrobium moniliforme Lipid peroxidation .OH O2^- POLYSACCHARIDES
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Infrared Spectra and Theoretical Calculations of BS2 and BS2-: Strong Pseudo Jahn-Teller Effect
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作者 赵杰 俞文杰 +1 位作者 黄腾飞 王雪峰 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2017年第6期678-684,I0002,共8页
Laser ablated boron atoms have been reacted with hydrogen sulfide and the reaction products condensed with argon at 4 K, which gave BS2, BS2-, HSBS, and HBS molecules. Reagent isotopic substitution (H2S, H234S, D2S, ... Laser ablated boron atoms have been reacted with hydrogen sulfide and the reaction products condensed with argon at 4 K, which gave BS2, BS2-, HSBS, and HBS molecules. Reagent isotopic substitution (H2S, H234S, D2S, 10 B, 11B) and variation of boron and hydrogen sulfide concentrations have been used to identify the major products. Both BS2-- and BS2 were identified as linear molecules with no significant difference in the structure parameters, but the B-S anti-symmetric stretching vibration of BS2 is significantly lower than that of BS2-, which is ascribed to pseudo Jahn-Teller effect. Theoretical calculation was employed to have an insight into the interaction nature of the bonds in the corresponding products. 展开更多
关键词 Matrix isolation Pseudo Jahn-Teller effect Multicenter bond
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Multichannel charge separation promoted ZnO /P25 heterojunctions for the photocatalytic oxidation of toluene 被引量:1
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作者 孔洁静 赖晓冬 +2 位作者 芮泽宝 纪红兵 季生福 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第6期869-877,共9页
The fabrication of multicomponent heterojunctions is an effective strategy to improve the performance of TiO2 based photocatalysts. We provide a new strategy for improving the charge separation and photocatalytic perf... The fabrication of multicomponent heterojunctions is an effective strategy to improve the performance of TiO2 based photocatalysts. We provide a new strategy for improving the charge separation and photocatalytic performance of ZnO /TiO2 composites by the formation of multichannel charge separated heterojunctions. ZnO /P25 composites were prepared by an incipient wetness impregnation method, and applied for the photocatalytic destruction of gaseous toluene. The ZnO /P25 composites consist of anatase TiO2(ATiO2), rutile TiO2(RTiO2) and hexagonal zincite structures. The parasitic phase of ZnO in P25 leads to the formation of ZnO(002)/ATiO2(101)/RTiO2(110) heterojunctions that exhibit enhanced light absorption and improved multichannel electron/hole separation. ZnO /P25 heterojunctions can completely oxidize toluene into CO2 and H2O under ultraviolet light irradiation at room temperature, and show enhanced photocatalytic activity in comparison with P25 owing to the efficient electron-hole separation. Such a multichannel charge separated design strategy may provide new insight into the design of highly effective photocatalysts and their potential technological applications. 展开更多
关键词 Titanium dioxide Zinc oxide TOLUENE PHOTOCATALYSIS HETEROJUNCTION Multichannel charge separation
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Numerical investigation of flow and heat transfer behind a two-dimensional backward-facing step equipped with a semi-porous baffle 被引量:3
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作者 Hamid-Reza BAHRAMI 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第11期3354-3367,共14页
The backward-facing step is a critical problem existing in many engineering and industrial applications.In this study,a semi-porous baffle(the root of the baffle is a porous medium and the tip is solid) is placed behi... The backward-facing step is a critical problem existing in many engineering and industrial applications.In this study,a semi-porous baffle(the root of the baffle is a porous medium and the tip is solid) is placed behind the step.The effects of the length of the porous part,and the baffle location on the energy transfer and pressure drop are studied in different Reynolds numbers(Re=100,200,300,400,500).The effect of the Darcy number of the porous medium on the aforementioned parameters is also investigated.Both the local maximum and average relative Nusselt numbers(divided by the Nusselt of the base case with no baffle at the same Reynolds) and relative pressure drop(calculated as the relative Nusselt number) are reported.The results show that by adoption of the proper length of the porous medium,the average relative and maximum local Nusselt numbers could be enhanced by 20% and 90%,respectively.Low permeable porous media give better energy transfer.For example,porous media with Da=10^(-5) give 30% better maximum local Nusselt number and about 7% higher average Nusselt number with respect to the same case with Da=10^(-2). 展开更多
关键词 porous media enhanced heat transfer BAFFLE backward-facing step two-dimensional channel
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Evaluation of genetic potential of the polyvoltine silkworm (Bombyx mori L.) germplasm and identification of parents for breeding programme 被引量:1
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作者 RAO C.G.P. SESHAGIRI S.V. +3 位作者 RAMESH C. IBRAHIM BASHA K. NAGARAJU H. CHANDRASHEKARAIAH 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2006年第3期215-220,共6页
In the present study, polyvoltine germplasm stock ofAndhra Pradesh State Sericulture Research and Development, Institute (APSSRDI) was evaluated for its performance based on quantitative and qualitative traits. Twen... In the present study, polyvoltine germplasm stock ofAndhra Pradesh State Sericulture Research and Development, Institute (APSSRDI) was evaluated for its performance based on quantitative and qualitative traits. Twenty-one oval and 10 peanut cocoon shaped lines were reared in different seasons of the year. Since the polyvoltines are non-diapausing, six generations were reared and evaluated for various economically important traits based on evaluation index and sub-ordinate function statistical methods. Ten top ranked lines obtained by using both the methods were identified as potential parental strains. Among oval lines, APMI4, APMI 1, APMIS, APMW9, and APMI9, and among peanut lines APMD5, APMDI, APMD3, APMD9 and APMD8 were selected as base material. The identified high yielding lines will be used in various breeding programmes as initial parents for the synthesis of superior polyvoltine breeds/hybrids. 展开更多
关键词 Polyvoltine SILKWORM GERMPLASM Performance EVALUATION
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A New Method for Hydrocarbon Detection Based on Multi-phase Theory 被引量:6
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作者 SaLiming Wangshangxui +2 位作者 MuYongguang LiangXiuwen LiuQuanxin 《Applied Geophysics》 SCIE CSCD 2004年第2期83-88,共6页
The hydrocarbon detection techniques used currently are generally based on the theory of single-phase medium, but hydrocarbon reservoir mostly is multi-phase medium, therefore, multisolutions and uncertainties are exi... The hydrocarbon detection techniques used currently are generally based on the theory of single-phase medium, but hydrocarbon reservoir mostly is multi-phase medium, therefore, multisolutions and uncertainties are existed in the result of hydrocarbon detection. This paper presents a fast way to detect hydrocarbon in accordance with BOIT theory and laboratory data. The technique called DHAF technique has been applied to several survey area and obtained good result where the coincidence rate for hydrocarbon detection is higher than other similar techniques. The method shows a good prospect of the application in hydrocarbon detecting at exploration stage and in reservoir monitoring at production stage. 展开更多
关键词 EXPLORATION multi-phase medium hydrocarbon detection reservoir.
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Optimization of hydrogen networks with multiple impurities and impurity removal 被引量:3
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作者 Xuexue Jia Guilian Liu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第9期1236-1242,共7页
To explore the effect of removing different impurities to hydrogen networks, an MINLP model is proposed with all matching possibilities and the trade-off between operation cost and capital cost is considered. Furtherm... To explore the effect of removing different impurities to hydrogen networks, an MINLP model is proposed with all matching possibilities and the trade-off between operation cost and capital cost is considered. Furthermore,the impurity remover, hydrogen distribution, compressor and pipe setting are included in the model. Based on this model, the impurity and source(s) that are in higher priority for impurity removal, the optimal targeted concentration, and the hydrogen network with the minimum annual cost can be identified. The efficiency of the proposed model is verified by a case study. 展开更多
关键词 Impurity removal MINLP model Optimization Multiple impurities Hydrogen network
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One-pot cascade conversion of xylose to furfuryl alcohol over a bifunctional Cu/SBA-15-SO3H catalyst 被引量:3
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作者 Tianyu Deng Guangyue Xu Yao Fu 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2020年第3期404-414,共11页
The conversion of hemicellulose-derived xylose to furfuryl alcohol is a practical procedure for producing value-added chemicals from biomass.In this study,a bifunctional Cu/SBA-15-SO3 H catalyst was employed for the o... The conversion of hemicellulose-derived xylose to furfuryl alcohol is a practical procedure for producing value-added chemicals from biomass.In this study,a bifunctional Cu/SBA-15-SO3 H catalyst was employed for the one-pot catalytic conversion of xylose to furfuryl alcohol with a yield of up to 62.6% at the optimized conditions of 140℃,4 MPa,and for 6 h in a biphasic water/n-butanol solvent.A high reaction temperature resulted in further hydrogenation to 2-methyl furan,while a high hydrogen pressure led to a side hydrogenation reaction to xylitol.The biphasic solvent allowed xylose solvation as well as furfuryl product extraction.The acidic-SO3 H sites and Cu sites co-existed,maintained a balance,and cooperatively catalyzed the cascade conversion.Excessive acidic sites and large pores could promote the xylose conversion,although a low furfuryl alcohol yield was obtained.This catalytic system could be potentially applied to the one-pot synthesis of furfuryl alcohol from hemicellulose-derived xylose. 展开更多
关键词 BIOMASS Furfuryl alcohol Heterogeneous catalysis One-pot synthesis XYLOSE
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Stabilization of heterogeneous hydrogenation catalysts for the aqueous-phase reactions of renewable feedstocks 被引量:2
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作者 Xiaoyan Liu Guojun Lan +3 位作者 Zhenqing Li Lihua Qian Jian Liu Ying Li 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2021年第5期694-709,共16页
The conversion of biomass-derived products to fine chemicals and fuels is extremely important for the utilization of renewable energy sources.Water is not only a by-product formed during the hydrogenation of biomass-d... The conversion of biomass-derived products to fine chemicals and fuels is extremely important for the utilization of renewable energy sources.Water is not only a by-product formed during the hydrogenation of biomass-derived oxygenated chemicals,but also an inexpensive and nontoxic solvent.The instability of solid catalysts for aqueous-phase reactions caused by metal leaching and the collapse of a catalyst support represents a significant challenge.In this work,various catalyst stabilization strategies including the nanospace and interfacial confinements that prevent sintering and leaching of metal nanoparticles as well as modification methods for increasing the support stability are summarized and systemically discussed.In addition,feasible approaches to designing stable and efficient heterogeneous catalysts for aqueous-phase reactions are proposed. 展开更多
关键词 Biomass conversion Heterogeneous catalysts Metal catalysts Aqueous-phase reactions Catalyst stability
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Extraction,Physiochemical Properties and Antibacterial Activities of Polysaccharides from Auricularia auricular 被引量:1
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作者 DENG Qinghua ZHAO Zhiyu ZHANG Zhongzhen 《Chinese Food Science》 2012年第1期37-39,53,共4页
[Objective] To explore the optimal conditions for extracting polysaccharide from Auricularia auricular, and to study its physiochemical properties and antibacterial activities. [ Method] The extraction conditions for ... [Objective] To explore the optimal conditions for extracting polysaccharide from Auricularia auricular, and to study its physiochemical properties and antibacterial activities. [ Method] The extraction conditions for Auricularia auricular polysaccharides were optimized by orthogonal test, and its physiochemical characteristics and antagonistic activities on bacteria and molds were tested. I-Result] The optimized condition was with sample to liquid ratio of 1 : 50, temperature of 90 ℃ and extraction time of 2.5 h. Under the optimized condition, the yield of pelysaccharide was 7.3%, with polysaccharide content of 77.81%. Containing aldose and amylase, the polysaccharides of Auncu/aria auricular was soluble in water. The inhibitory effect on bacteria was significantly stronger than on molds that the minimum diameter of inhibition zone for bacteria is 12.7 mm, while 7.9 mm for the molds. [ Conclusion] This study provides scientific basis for the development and utilization of Auricularia auricular polysaccharides. 展开更多
关键词 Auricularia auricular Fruit body POLYSACCHARIDES Extraction process Physicochemical property Antibacterial activity China
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Properties of Polysaccharides in Several Seaweeds from Atlantic Canada and Their Potential Anti-Influenza Viral Activities 被引量:6
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作者 JIAO Guangling YU Guangli +3 位作者 WANG Wei ZHAO Xiaoliang ZHANG Junzeng Stephen H. Ewart 《Journal of Ocean University of China》 SCIE CAS 2012年第2期205-212,共8页
To explore the polysaccharides from selected seaweeds of Atlantic Canada and to evaluate their potential anti-influenza virus activities, polysaccharides were isolated from several Atlantic Canadian seaweeds, includin... To explore the polysaccharides from selected seaweeds of Atlantic Canada and to evaluate their potential anti-influenza virus activities, polysaccharides were isolated from several Atlantic Canadian seaweeds, including three red algae (Polysiphonia lanosa, Furcellaria lumbricalis, and Palmaria palmata), two brown algae (Ascophyllum nodosum and Fucus vesiculosus), and one green alga (Ulva lactuca) by sequential extraction with cold water, hot water, and alkali solutions. These polysaccharides were ana-lyzed for monosaccharide composition and other general chemical properties, and they were evaluated for anti-influenza virus activities. Total sugar contents in these polysaccharides ranged from 15.4% (in U. lactuca) to 91.4% (in F. lumbricalis); sulfation level was as high as 17.6% in a polysaccharide from U. lactuca, whereas it could not be detected in an alikali-extract from P. palmaria. For polysaccharides from red seaweeds, the main sugar units were sulfated galactans (agar or carrageenan) for P. lanosa, F. lumbricalis, and xylans for P. palmata. In brown seaweeds, the polysaccharides largely contained sulfated fucans, whereas the polysaccharides in green seaweed were mainly composed of heteroglycuronans. Screening for antiviral activity against influenza A/PR/8/34 (H1N1) virus revealed that brown algal polysaccharides were particularly effective. Seaweeds from Atlantic Canada are a good source of marine polysaccharides with potential antiviral properties. 展开更多
关键词 POLYSACCHARIDES anti-influenza viral activity monosaccharide composition H1N1
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Numerical analysis on forced convection enhancement in an annulus using porous ribs and nanoparticle addition to base fluid 被引量:6
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作者 Majid SIAVASHI Hamid Reza TALESH BAHRAMI +1 位作者 Ehsan AMINIAN Hamid SAFFARI 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第5期1089-1098,共10页
Miniaturization of electronic equipment has forced researchers to devise more effective methods for dissipating the generated heat in these devices.In this study,two methods,including porous media inserting and adding... Miniaturization of electronic equipment has forced researchers to devise more effective methods for dissipating the generated heat in these devices.In this study,two methods,including porous media inserting and adding nanoparticles to the base fluid,are used to improve heat transfer in an annulus heated on both walls.To study porous media insert,porous ribs are used on the outer and inner walls independently.The results show that when porous ribs are placed on the outer wall,although the heat transfer enhances,the pressure drop increment is so considerable that performance number (the ratio of heat transfer enhancement pressure increment,PN) is less than unity for all porous rib heights and porous media permeabilities that are studied.On the other hand,the PN of cases where porous ribs were placed on the inner wall depends on the Darcy number (Da).For example,for ribs with Da=0.1 and Da=0.0001,the maximum performance number,PN=4,occurs at the porous ribs height to hydraulic diameter ratios H/Dh=1 and H/Dh=0.25.Under these conditions,heat transfer is enhanced by two orders of magnitude.It is found that adding 5% nanoparticles to the base fluid in the two aforementioned cases improves the Nusselt number and PN by 10%–40%. 展开更多
关键词 NANOFLUID porous media ANNULUS heat transfer enhancement internal flow
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Straightforward synthesis of beta zeolite encapsulated Pt nanoparticles for the transformation of 5-hydroxymethyl furfural into 2,5-furandicarboxylic acid 被引量:2
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作者 Xiaoling Liu Lei Chen +3 位作者 Hongzhong Xu Shi Jiang Yu Zhou Jun Wang 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2021年第6期994-1003,共10页
Encapsulating noble metal nanoparticles(NPs)within the zeolite framework enhances the stability and accessibility of active sites;however,direct synthesis remains a challenge because of the easy precipitation of noble... Encapsulating noble metal nanoparticles(NPs)within the zeolite framework enhances the stability and accessibility of active sites;however,direct synthesis remains a challenge because of the easy precipitation of noble metal species under strong alkali crystallization conditions.Herein,beta zeolite-encapsulated Pt NPs(Pt@Beta)were synthesized via a hydrothermal approach involving an unusual acid hydrolysis preaging step.The ligand—(3-mercaptopropyl)trimethoxysilane—and Pt precursor were cohydrolyzed and cocondensed with a silica source in an initially weak acidic environment to prevent colloidal precipitation by enhancing the interaction between the Pt and silica species.Thus,the resultant 0.2%Pt@Beta was highly active in the transformation of 5-hydroxymethylfurfural into 2,5-furandicarboxylic acid(FDCA)under atmospheric O2 conditions by using water as the solvent while stably evincing a high yield(90%)associated with a large turnover number of 176.The excellent catalysis behavior is attributable to the enhanced stability that inhibits Pt leaching and strengthens the intermediates that accelerate the rate-determining step for the oxidation of 5-formyl-2-furan carboxylic acid into FDCA. 展开更多
关键词 Hydrothermal synthesis ZEOLITE Noble metal nanoparticles Heterogeneous catalysis Biomass conversion
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Melting heat transfer with radiative effects and homogeneous–heterogeneous reaction in thermally stratified stagnation flow embedded in porous medium 被引量:4
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作者 M.JAVED M.FAROOQ +1 位作者 S.AHMAD Aisha ANJUM 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第11期2701-2711,共11页
The present article deals with thermally stratified stagnation-point flow saturated in porous medium on surface of variable thickness along with more convincing and reliable surface condition termed as melting heat tr... The present article deals with thermally stratified stagnation-point flow saturated in porous medium on surface of variable thickness along with more convincing and reliable surface condition termed as melting heat transfer.Homogeneous–heterogeneous reaction and radiative effects have been further taken into account to reconnoiterproperties of heat transfer.Melting heat transfer and phenomenon of homogeneous–heterogeneous reaction have engrossed widespread utilization in purification of metals,welding process,electroslag melting,biochemical systems,catalysis and several industrial developments.Suitable transformations are utilized to attain a scheme of ordinary differential equations possessing exceedingly nonlinear nature.Homotopic process is employed to develop convergent solutions of the resulting problem.Discussion regarding velocity,thermal field and concentration distribution for several involved parameters is pivotal part.Graphical behaviors of skin friction coefficient and Nusselt number are also portrayed.Concentration of the reactants is found to depreciate as a result of strength of both heterogeneous and homogeneous reaction parameters.With existence of melting phenomenon,declining attitude of fluid temperature is observed for higher radiation parameter. 展开更多
关键词 melting heat transfer porous medium stagnation point variable sheet thickness homogeneous– heterogeneous reaction
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Interfacial-interaction-induced fabrication of biomass-derived porous carbon with enhanced intrinsic active sites 被引量:2
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作者 Wenjuan Zhang Pei Jing +3 位作者 Juan Du Shujie Wu Wenfu Yan Gang Liu 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第8期2231-2239,共9页
Carbon catalysis is an attractive metal-free catalytic transformation,and its performance is significantly dependent on the number of accessible active sites.However,owing to the inherent stability of the C-C linkage,... Carbon catalysis is an attractive metal-free catalytic transformation,and its performance is significantly dependent on the number of accessible active sites.However,owing to the inherent stability of the C-C linkage,only limited active sites at the edge defects of the basal plane can be obtained even after a harsh oxidation treatment.In this study,the concept of interfacial interactions was adopted to propose an efficient strategy to develop highly active carbon catalysts.The alumina/carbon interface formed in situ acted as a cradle for the generation of oxygen-containing functional groups.In the absence of oxidation treatment,the concentration of oxygen-containing functional groups and the specific surface area can reach 1.27 mmol·g^(-1) and 2340 m^(2)·g^(-1),respectively,which are significantly higher than those of carbon prepared by traditional hard template methods.This active carbon shows a significant enhancement in catalytic performance in the oxidative coupling of amine to imine,about 22-fold higher than that of a well-known graphite oxide catalyst.Such interfacial interaction strategies are based on sustainable carbon sources and can effectively tune the porous structure of carbon in the micro-and meso-ranges.This conceptual finding offers new opportunities for the development of high-performance carbon-based metal-free catalysts. 展开更多
关键词 Interfacial interaction Porous carbon Biomass Surface functionality IMINES
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Shortcut Procedure for Inverted Batch Distillation Column (I) Multicomponent Ideal System 被引量:12
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作者 许松林 HectorE.Salomone OscarA.Iribarren 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2001年第1期28-33,共6页
Inverted batch distillation column(stripper) is opposed to a conventional batch distillation col-umn(rectifier). It has a storage vessel at the top and products leave the column at the bottom. The batch stripper is fa... Inverted batch distillation column(stripper) is opposed to a conventional batch distillation col-umn(rectifier). It has a storage vessel at the top and products leave the column at the bottom. The batch stripper is favourable to separate mixtures with a small amount of light components by removing the heavy components as bottom products. In this paper, we are presenting a shortcut procedure based on our earlier work for design and simulation of the inverted batch distillation column, which is equivalent to the Fenske-Underwood-Gilliland procedure for continuous distillation. Given a separation task, we propose to compute the minimum number of stages(Nbmin) and the minimum reboil ratio(Rbmin) required in a batch stripper,which are the stages and reboil ratio required in a hypothetical inverted batch distillation column operating in total reboil ratio or having an infinite number of stages, respectively. Then, it is shown that the performance of inverted batch columns with a finite number of stages and reboil ratios could be correlated in Gilliland coordinates with the minimum stages Nbmin and the minimum reboil ratio Rbmin. 展开更多
关键词 inverted batch distillation column STRIPPER shortcut procedure
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Dynamic change of protein polypeptide of Ginkgo biloba seed during germination
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作者 GUO Hong-yan LI Sheng-ping PENG Fang-ren 《Journal of Forestry Research》 SCIE CAS CSCD 2007年第1期35-38,共4页
The dynamic changes of protein polypeptide in endosperms of Gingkgo biloba seeds during seed germination were studied by SDS-PAGE and two-dimensional gel electrophoresis (2-DE). The results showed that 80 kinds of p... The dynamic changes of protein polypeptide in endosperms of Gingkgo biloba seeds during seed germination were studied by SDS-PAGE and two-dimensional gel electrophoresis (2-DE). The results showed that 80 kinds of protein spots in endosperms of Gingkgo biloba were clear observed in the 2-DE spectrum. Protein molecular weights were in the range of 26-52kD, and their isoelectric points were in the range of 5.8-7.8. In the course of seed germination, 13 kinds of proteins were degraded, and 13 kinds of proteins were synthesized; 7 kinds of proteins with different molecular weights and isoelectric points of 35kD/pIr.8, 31kD/pIr.8, 29kD/pIr.8, 33kD/pI6.6, 33kD/pI 6.4, 34kD/pI7.7 and 31kD/pI7.7 were identified primarily as vegetative storage proteins (VSPs). 展开更多
关键词 Ginkgo biloba seed GERMINATION PROTEIN ELECTROPHORESIS
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Application of grey relational analysis in sheet metal forming for multi-response quality characteristics 被引量:5
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作者 XIE Yan-min YU Hu-ping +1 位作者 CHEN Jun RUAN Xue-yu 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第5期805-811,共7页
The theory of grey systems is a new technique for performing prediction, relational analysis and decision making in many areas. In this paper, the use of grey relational analysis for optimizing the square hole flangin... The theory of grey systems is a new technique for performing prediction, relational analysis and decision making in many areas. In this paper, the use of grey relational analysis for optimizing the square hole flanging process parameters with considerations of the multiple response (the average flanging height, regular flanging and maximum strain) is introduced. Various flanging parameters, such as the blank inner radius rb, blank inner width B0, are considered. An orthogonal array is used for the experimental design. Multiple response values are obtained using finite element analysis (FEA). Optimal process parameters are determined by the grey relational grade obtained from the grey relational analysis for multi-performance characteristics (flanging height, regular flanging and maximum strain). Analysis of variance (ANOVA) for the grey relational grade is implemented. The results showed good agreement with the experiment result. Grey relational analysis can be applied in multiple response optimi-zation designs. 展开更多
关键词 Grey relational analysis FLANGING Multiple response Optimization design
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