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Assessing and Improving the Quality of Undergraduates in Preschool Education Programs in China:The Course Experience
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作者 Linxi Zhang Lei Zheng Ying Zhou 《教育技术与创新》 2024年第3期31-46,共16页
This study investigated the current status of course satisfaction among 416 undergraduate students majoring in preschool education from four universities in China.And it explored the predictive effects of five influen... This study investigated the current status of course satisfaction among 416 undergraduate students majoring in preschool education from four universities in China.And it explored the predictive effects of five influencing factors(teacher instruction,course management,course setting,course environment,and course resources)on student satisfaction.Through SPSS data analysis,the findings revealed that:1.the mean value of course experience was M=3.861(out of 5);2.there were differences in the satisfaction of undergraduate students'course experience by different background variables;3.course,course resources,and loyalty had significant predictive power on undergraduate students'satisfaction with course experience;4.instructor instruction(TI)did not significantly predict students'satisfaction with course experience(SCES)(p>0.001);5.Faculty instruction(TI)in this study had the highest mean satisfaction score(M=4.191)and the mean satisfaction score was only(M=3.861).The results show that the current status of course satisfaction among Chinese preschool undergraduates is at an moderate level,and there is more space for improvement;although students'satisfaction with teacher instruction(TI)is high,effective teacher instruction does not have a substantial impact on the acquisition of SCES or general competencies,and this passive learning and teaching style leads to a lack of independent learning and active participation among Chinese preschool undergraduate students. 展开更多
关键词 Higher education Preschool education program SATISFACTION Course experience
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Water Quality Evaluation of Duyun-Kaili Section in the Upper Reaches of the Qingshui River Basin
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作者 SHANG Hailong XU Ruifang XIAO Yuexing 《Journal of Landscape Research》 2018年第4期86-89,共4页
The fuzzy mathematic model was used to evaluate the water quality of six sections in the upper reaches of the Qingshui River Basin. The results showed that tiie water of grade I accounted for a high proportion, with m... The fuzzy mathematic model was used to evaluate the water quality of six sections in the upper reaches of the Qingshui River Basin. The results showed that tiie water of grade I accounted for a high proportion, with mild pollution and strong self-deaning ability; the pollutants (f.g. ammonium nitrogen, total phosphorus and fluoride) at each section mainly came from phosphate mines and phosphorus chemical companies; and the water quaEty among different sections was in the order Chayuan, Xingren Bridge, Xiasi, Locomotive Section, Yingpan, Panghai (from superiority to inferiority). This study has important reference values fof improving the water envifonment, saf^uarding the safely of drinkiiig water supply and scientifically preventing and conttolling water pollution, in the basin. 展开更多
关键词 Fuzzy comprehensive evaluation model Watef quality evaluation Duyun-Kaili section of Qingshui River
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Two-dimensional CrP_(2) with high specific capacity and fast charge rate for lithium-ion battery
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作者 王晓允 荆涛 梁冬梅 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第6期489-494,共6页
The electrode material is regarded as one of the key factors that determine the performance of lithium-ion batteries(LIBs).However,it is still a challenge to search for an anode material with large capacity,low diffus... The electrode material is regarded as one of the key factors that determine the performance of lithium-ion batteries(LIBs).However,it is still a challenge to search for an anode material with large capacity,low diffusion barrier,and good stability.In the present work,two new CrP_(2) monolayers(Pmmn-CrP_(2) and Pmma-CrP_(2)) are predicted by means of first principles swarm structure search.Our study shows that both the two CrP_(2) monolayers have high dynamical and thermal stability,as well as excellent electron conductivity.Additionally,Pmmn-CrP_(2) exhibits a remarkably high storage capacity of 705 mA·h·g^(-1) for Li,meanwhile the diffusion energy barrier of Li on the surface of this monolayer is 0.21 eV,ensuring it as a high-performance anode material for LIBs.We hope that our study will inspire researchers to search for new-type two-dimensional(2D) transition metal phosphides for the electrode materials of LIB s. 展开更多
关键词 lithium-ion battery electronic structure first principles
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The Crosslinking Mechanism of Camellia Oleifera Protein Adhesive with Amine Resins by ^(13)C-NMR and ESI-MS
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作者 DENG Xue ZHANG Bengang +3 位作者 LIANG Jiankun LI Lifen WU Zhigang LEI Hong 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2023年第2期460-466,共7页
A new protein wood adhesive was studied with Camellia oleifera protein.Formaldehyde and N-(2)-L-Ala-L-Gln(LAG)were used as the model compounds of amino resins and Camellia oleifera protein,aiming to provide scientific... A new protein wood adhesive was studied with Camellia oleifera protein.Formaldehyde and N-(2)-L-Ala-L-Gln(LAG)were used as the model compounds of amino resins and Camellia oleifera protein,aiming to provide scientific foundations for the improvement and applications of Camellia oleifera protein adhesive by the reaction of model compounds.The experimental results demonstrate that,under alkaline conditions,formaldehyde is easier to react with Camellia oleifera protein by quicker reaction and lower curing temperature.Under acid conditions,amino hydroxymethylated structure of aliphatic series from LAG is difficult to form stable reactive intermediates and further polycondensation.Hydroxymethylation of end acylamino and peptide bond amino from LAG is relatively weak.Under alkaline conditions,the free aliphatic amino and acylamino of LAG both can make hydroxymethylation reaction with formaldehyde.In the polycondensation,hydroxymethyl amide is the initial structure and the reactive intermediate is produced by E1cb reaction of hydroxymethyl amide.Methylene bridge bonds and methylene ether bonds are structures of the polycondensation products,which are competing reactions.The former is mainly formed by the reaction between alkaline reactive intermediate and amino of aliphatic series,and the latter is produced by the reaction of reactive intermediate and amino of hydroxymethyl aliphatic series with hydroxymethyl amide. 展开更多
关键词 Camellia oleifera protein wood adhesive ESI-MS NMR
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Investigation and Identification of Fungal Diseases of Kiwifruit in Qiandongnan Prefecture
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作者 Guohui ZHANG Huanxian GU +2 位作者 Xiangyang LI Shengli SI Wenhua ZHANG 《Plant Diseases and Pests》 CAS 2023年第1期1-5,共5页
[Objectives]The paper was to investigate and identify the fungal diseases of wild and red heart kiwifruit in Qiandongnan Prefecture.[Methods]The pathogenic fungi were isolated from diseased leaves and fruits of wild a... [Objectives]The paper was to investigate and identify the fungal diseases of wild and red heart kiwifruit in Qiandongnan Prefecture.[Methods]The pathogenic fungi were isolated from diseased leaves and fruits of wild and red heart kiwifruit by tissue separation method.DNA sequencing was carried out by using the sequence analysis of ribosomal r DNA-ITS region,and molecular evolutionary trees were built by using MEGA 4.0 software.Finally,the pathogenic fungi were classified and identified by combining morphological observation.[Results]The main fungal diseases were anthracnose caused by Colletotrichum gloeosporioides on wild kiwifruit,fruit anthracnose caused by C.acutatum on red heart kiwifruit,leaf soft rot caused by Fusarium incarnatum on red heart kiwifruit,and brown spot caused by Alternaria alternata on red heart kiwifruit.[Conclusions]The study may provide some theoretical basis for the control of kiwifruit diseases in Qiandongnan Prefecture. 展开更多
关键词 Wild kiwifruit Red heart kiwifruit Fungal disease PATHOGEN IDENTIFICATION Qiandongnan Prefecture
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Crosslinking Mechanism of Soy Protein-based Adhesives based on Glyoxal and a Compound of Protein Model
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作者 曹龙 LIANG Jiankun +3 位作者 ZHANG Qiaoyan XI Xuedong 吴志刚 雷洪 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2023年第4期942-950,共9页
The crosslinking mechanism of glyoxal and asparagine was analyzed,and the relationship between the mechanism and practical performances of soy protein-based adhesives was also discussed.It is shown that when pH=1 and ... The crosslinking mechanism of glyoxal and asparagine was analyzed,and the relationship between the mechanism and practical performances of soy protein-based adhesives was also discussed.It is shown that when pH=1 and 3,glyoxal reacted with asparagine in the form of major cyclic ether compounds.When pH=5,glyoxal reacted with asparagine in two structural forms of sodium glycollate and cyclic ether compounds.However,amidogens of asparagine were easy to develop protonation under acid conditions.Supplemented by the instability of cyclic ether compounds,the reaction activity and reaction degree between glyoxal and asparagine were relatively small.Under alkaline conditions,glyoxal mainly reacted with asparagine in the form of sodium glycollate.With the increase of pH,the polycondensation was more sufficient and the produced polycondensation products were more stable.The reaction mechanism between glyoxal and asparagine had strong correspondence to the practical performances of the adhesives.Glyoxal solution could develop crosslinking reactions with soy protein under both acid and alkaline conditions.Bonding strength and water resistance of the prepared soy protein-based adhesives were increased significantly.When pH>7,glyoxal had relatively high reaction activity and reaction intensity with soy protein,and the prepared adhesives had high crosslinking density and cohesion strength,showing relatively high bonding strength,water resistance and thermal stability. 展开更多
关键词 soy protein wood adhesives GLYOXAL model compounds CROSSLINKING
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Nail Holding Performance of Self-Tapping Screws on Masson Pine and Chinese Fir Dimension Lumbers
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作者 De Li Bengang Zhang +7 位作者 Yuan Tu Guoming Xiao Meifen Tian Xiaoxue Xu Xiao Zhong Qiaoyan Zhang Zhigang Wu Jiankun Liang 《Journal of Renewable Materials》 EI 2023年第10期3725-3738,共14页
Screw connection is a type most commonly applied to timber structures.As important commercial tree species in China,Masson pine and Chinese fir have the potential to prepare wood structures.In this study,the effects o... Screw connection is a type most commonly applied to timber structures.As important commercial tree species in China,Masson pine and Chinese fir have the potential to prepare wood structures.In this study,the effects of the diameter of the self-tapping screw and the guiding bores on the nail holding performance on different sections of Masson pine and Chinese fir dimension lumbers were mainly explored.The results showed that:(1)The nail holding strength of the tangential section was the maximum,followed by that of the radial section,and that of the cross section was the minimum.(2)The nail holding strength of Masson pine was higher than that of Chinese fir.(3)The nail holding strength grew with the increase in the diameter of self-tapping screws,but a large diameter would lead to plastic cracking of the timber,thus further affecting the nail holding strength.Masson pine and Chinese fir reached the maximum nail holding strength when the diameter of self-tapping screws was 3.5 mm.(4)Under a large diameter of screws,prefabricated guiding bores could mitigate timber cracking and improve its nail holding strength.(5)Prefabricated guiding bores were more necessary for the screw connection of Masson pine.The results obtained could provide a scientific basis for the screw connection design of Masson pine and Chinese fir timber structures. 展开更多
关键词 Masson pine Chinese fir self-tapping screws nail holding performance
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张毕来与台湾义勇队的筹建与宣传 被引量:2
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作者 刘鹤 LIU He 《浙江师范大学学报(社会科学版)》 北大核心 2013年第5期82-87,共6页
在强烈的爱国心的驱使下,在中国共产党的正确领导下,出生于贵州的张毕来致力筹建、积极宣传台湾义勇队。他全程参与、积极筹划了台湾义勇队的组建,并通过撰写文章、广泛演讲、出版《台湾先锋》等活动,为宣传台湾革命和台湾义勇队作出了... 在强烈的爱国心的驱使下,在中国共产党的正确领导下,出生于贵州的张毕来致力筹建、积极宣传台湾义勇队。他全程参与、积极筹划了台湾义勇队的组建,并通过撰写文章、广泛演讲、出版《台湾先锋》等活动,为宣传台湾革命和台湾义勇队作出了巨大贡献。 展开更多
关键词 张毕来 台湾义勇队 筹建 宣传
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A draft genome, resequencing, and metabolomes reveal the genetic background and molecular basis of the nutritional and medicinal properties of loquat (Eriobotrya japonica (Thunb.) Lindl) 被引量:4
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作者 Yunsheng Wang 《Horticulture Research》 SCIE 2021年第1期3193-3210,共18页
Loquat(Eriobotrya japonica)is a popular fruit and medicinal plant.Here,a high-quality draft genome of the E.japonica‘Big Five-pointed Star’cultivar that covers~98%(733.32Mb)of the estimated genome size(749.25 Mb)and... Loquat(Eriobotrya japonica)is a popular fruit and medicinal plant.Here,a high-quality draft genome of the E.japonica‘Big Five-pointed Star’cultivar that covers~98%(733.32Mb)of the estimated genome size(749.25 Mb)and contains a total of 45,492 protein-coding genes is reported.Comparative genomic analysis suggests that the loquat genome has evolved a unique genetic mechanism of chromosome repair.Resequencing data from 52 loquat cultivars,including 16 white-fleshed and 36 yellow-fleshed variants,were analyzed,and the flower,leaf,and root metabolomes of‘Big Five-pointed Star’were determined using a UPLC-ESI-MS/M system.A genome-wide association study identified several candidate genes associated with flesh color in E.japonica,linking these phenotypes to sugar metabolism.A total of 577 metabolites,including 98 phenolic acids,95 flavonoids,and 28 terpenoids,were found,and 191 metabolites,including 46 phenolic acids,33 flavonoids,and 7 terpenoids,showed no differences in concentration among the leaves,roots,and flowers.Candidate genes related to the biosynthesis of various medicinal ingredients,such as phenolics,flavonoids,terpenoids,and polysaccharides,were identified.Some of these genes were confirmed to be members of expanding gene families,suggesting that the high concentrations of beneficial metabolites in loquat may be associated with the number of biosynthetic genes in this plant.In summary,this study provides fundamental molecular insights into the nutritional and medical properties of E.japonica. 展开更多
关键词 PHENOLIC linking roots
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Study on Camellia Oleifera Protein based Wood Adhesive by Epoxy Resin and Its Crosslinking Mechanism 被引量:5
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作者 CHEN Sicheng LIANG Jiankun +4 位作者 ZHANG Bengang WU Zhigang LEI Hong LI Lifen YANG Shoulu 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2021年第4期607-613,共7页
Epoxy resin (EPR) was used to crosslink with Camellia oleifera Abel.protein to prepare wood adhesive,and the bonding performance and curing characteristics of which were mainly investigated,and the synthesis mechanism... Epoxy resin (EPR) was used to crosslink with Camellia oleifera Abel.protein to prepare wood adhesive,and the bonding performance and curing characteristics of which were mainly investigated,and the synthesis mechanism was also discussed by using model compounds.The experimental results show that EPR can significantly improve the bonding performance of Camellia oleifera Abel.protein-based adhesive,and the maximum of which reaches 0.72 MPa satisfies the strength requirement of Type II plywood in GB/T 17657-2013.After alkali treatment,the protein can more easily crosslink with EPR at low curing temperature,and the adhesive has high degree of crystallinity of curing products,high degree of crosslinking reaction,and high bonding strength.The reaction mechanism of EPR-modified Camellia oleifera Abel.protein adhesive can be divided into resinification phase and curing phase. 展开更多
关键词 Camellia oleifera protein epoxy resin CROSSLINKING wood adhesive
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Study on the Soy Protein-Based Adhesive Cross-Linked by Glyoxal 被引量:6
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作者 Zhigang Wu Jiankun Liang +3 位作者 Hong Lei Bengang Zhang Xuedong Xi Lifen Li 《Journal of Renewable Materials》 SCIE EI 2021年第2期205-218,共14页
Based on the ESI-MS and ^(13)C-NMR analysis of the forms of glyoxal in acidic and alkaline solutions,the soy-based adhesive cross-linked by glyoxal was prepared in this work.The results showed that glyoxal existed in ... Based on the ESI-MS and ^(13)C-NMR analysis of the forms of glyoxal in acidic and alkaline solutions,the soy-based adhesive cross-linked by glyoxal was prepared in this work.The results showed that glyoxal existed in water in different forms at different pH levels.Under alkaline conditions,glyoxal transformed to glycolate through the intramolecular disproportionation reaction.Under acidic conditions,although some of glyoxal transformed to glycolate as what happened under alkaline conditions,most of glyoxal molecules existed in the form of fiveor six-membered cyclic ether structure.No ethylene tetraol or free aldehyde group was actually detected under these conditions.Although glyoxal reacted with soy protein under both acidic and alkaline conditions,alkaline conditions were more favorable for the improvement of mechanical performance and water resistance of soybased adhesives than acid conditions. 展开更多
关键词 GLYOXAL soy protein-based adhesive CROSS-LINK
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Soil microbial activity and nutrients of evergreen broad-leaf forests in mid-subtropical region of China 被引量:5
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作者 Zhangquan Zeng Silong Wang +4 位作者 Canming Zhang Hong Tang Xiquan Li Zijian Wu Jia Luo 《Journal of Forestry Research》 SCIE CAS CSCD 2015年第3期673-678,共6页
To better understand the effects of forest suc- cession on soil microbial activity, a comparison of soil microbial properties and nutrients was conducted between three forest types representing a natural forest succes... To better understand the effects of forest suc- cession on soil microbial activity, a comparison of soil microbial properties and nutrients was conducted between three forest types representing a natural forest succession chronosequence. The study compared a pine (Pinus mas- soniana) forest (PF), a pine and broadleaf mixed forest (MF) and an evergreen broadleaf forest (BF), in the Yingzuijie Biosphere Reserve, Hunan Province, China. Results showed that soil nutrients in the MF and BF plots were higher than in the PF plots. The range in microbial biomass carbon followed a similar pattem with Be havingthe greatest values, 522-1022 mg kg-1, followed by Mr 368-569 mg kg-1, and finally, PF 193--449 mg kg-1. Soil nutrients were more strongly correlated with microbial biomass carbon than basal respiration or metabolic quo- tient. Overall, forest succession in the study site improved soil microbial properties and soil fertility, which in turn can increase primary productivity and carbon sequestration. 展开更多
关键词 Keywords qCO2 Soil microbial biomass C Soil nutrient
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Synthesis of Mesoporous Chromium Aluminophosphate (CrAlPO) via Solid State Reaction at Low Temperature 被引量:2
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作者 刘少友 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2012年第2期337-345,共9页
Mesoporous chromium aluminophosphate (CrAIPO) was successfully synthesized via solid state reaction (SSR) route at low temperature in the presence of a cationic surfactant cetyltrimethyl ammonium bromide (CTAB) ... Mesoporous chromium aluminophosphate (CrAIPO) was successfully synthesized via solid state reaction (SSR) route at low temperature in the presence of a cationic surfactant cetyltrimethyl ammonium bromide (CTAB) and inorganic sources such as A1C13 · 6H20, CrCI3 · 6H20 and NaH2PO4 · 2H20. Characterizations by means of powder X-ray diffraction (XRD), N2 adsorption- desorption, high resolution transmission electron microscopy (HR-TEM), scanning electron micrography (SEM), energy dispersion spectroscopy (EDS), thermo-gravimetry (TG), Fourier transform infrared spectroscopy (FT-IR), and ultraviolet visible light spectroscopy (UV-Vis) were carried out to understand both the pore characteristics and electron transition route of these obtained materials. The experimental results show that the meso-CrA1PO materials with various Cr/A1 molar ratios possess a mesostructure and a specific surface area of 193 to 310 m2/g corresponding to an average pore size of 5.5 to 2.2 rim, respectively. The maxium content of Cr in meso-CrA1PO materials synthesized via SSR route can achieve 16.7wt%, being significantly higher than that of the meso-CrA1PO prepared via a conventional sol-gel route. Meanwhile, the formation mechanism of the meso-CrA1PO was also proposed. 展开更多
关键词 MESOPOROUS chromium aluminophosphate solid state reaction low temperature
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THE NORMAL FAMILITY OF MERMORPHIC FUNCTIONS 被引量:2
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作者 韩明华 顾永兴 《Acta Mathematica Scientia》 SCIE CSCD 2008年第4期759-762,共4页
Let F be a family of mermorphic functions in a domain D, and let a, b, c be complex numbers, a ≠ b. If for each f ∈ F, the zeros of f-c are of multiplicity ≥ k + 1, and -↑Ef(k)(a) belong to -↑Ef (a), -↑Ef... Let F be a family of mermorphic functions in a domain D, and let a, b, c be complex numbers, a ≠ b. If for each f ∈ F, the zeros of f-c are of multiplicity ≥ k + 1, and -↑Ef(k)(a) belong to -↑Ef (a), -↑Ef(k)(b)belong to -↑Ef (b), then F is normal in D. 展开更多
关键词 Mermorphic functions normal family shared values
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Study on Enzymatic Kinetics of Nephelium lappaceum Polyphenol Oxidase 被引量:2
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作者 Lunpei LIU Wenhua ZHANG 《Agricultural Biotechnology》 CAS 2012年第4期39-42,共4页
[Objective] This study aimed to investigate the enzymatic kinetics of polyphenol oxidase in peel of Nephelium lappaceum to explore the environmental factors affecting its catalytic activity. [ Method ] With N. lappace... [Objective] This study aimed to investigate the enzymatic kinetics of polyphenol oxidase in peel of Nephelium lappaceum to explore the environmental factors affecting its catalytic activity. [ Method ] With N. lappaceum peel as the experimental material and catechol as substrate, effects of temperature, pH, four inhibitors (EDTA, Vc, sodium bisulfite and citric acid) and substrate concentration on the activity of polyphenol oxidase were investigated. [ Result] The optimal temperature for polyphenol oxidase in N. lappaceum peel was 40 %, and the optimal pH was 6.8. EDTA, Vc, sodium bisulfite and citric acid all showed ideal in- hibitory effects on the activity of polyphenol oxidase; specifically, EDTA had the strongest inhibitory effect. [ Conclusion] At low temperature, EDTA, Vc, sodi- um bisulflte and citric acid with certain concentrations can inhibit the catalytic activity of polyphenol oxidase in peel of N. lappaceum, extend the storage and trans- portation time of N. lappaceum fruit, and inhibit the browning. This study provides theoretical basis for the development and utilization of polyphenol oxidase in peel of N. lappaceum. 展开更多
关键词 Nephelium lappaceum Polyphenol oxidase Enzymatic kinetics
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Optimization of Fenton pretreatment for 2-chlorophenol solution 被引量:1
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作者 贺仲兵 刘云国 肖玉 《Journal of Central South University》 SCIE EI CAS 2013年第10期2791-2795,共5页
Fenton oxidation was used as the pretreatment of 2-chlorophenol wastewater with the objective of dechlorination, as it was considered that after breakage of aryl—Cl bond, the generated intermediates may be easily bio... Fenton oxidation was used as the pretreatment of 2-chlorophenol wastewater with the objective of dechlorination, as it was considered that after breakage of aryl—Cl bond, the generated intermediates may be easily biodegraded. Hence, the optimization of pH and the low Fenton reagent doses for dechlorination was investigated. More than 99% dechlorination is obtained at the optimal pH 4 and the Fenton reagent doses of 86 mmol/L H2 O2 and 2.87 mmol/L Fe2+. The corresponding 2-chlorophenol is degraded completely, 80.02% COD is also removed, and the biodegradability, evaluated in terms of the BOD5 /COD ratio, is increased up to 0.41. To test the effect of this pretreatment, the pretreated 2-chlorophenol wastewater was fed to a sequencing batch reactor(SBR). The results show that complete mineralization is achieved. It is demonstrated that, for the treatment of recalcitrant compounds like 2-chlorophenol, the Fenton pretreatment could be quite effective and economical for enhancing the biodegradability in a Fenton-biological coupled system. 展开更多
关键词 2-CHLOROPHENOL Fenton-biological coupled system DECHLORINATION sequencing BATCH reactor(SBR) BIODEGRADABILITY
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Plasma Treatment Induced Chemical Changes of Alkali Lignin to Enhance the Performances of Lignin-Phenol-Formaldehyde Resin Adhesive 被引量:2
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作者 Zhigang Wu Sicheng Chen +5 位作者 Jiankun Liang Lifen Li Xuedong Xi Xue Deng Bengang Zhang Hong Lei 《Journal of Renewable Materials》 SCIE EI 2021年第11期1959-1972,共14页
Alkali lignin was processed by plasma and then used in modification of phenol formaldehyde resin in this study.Chemical structural changes of lignin which was processed by plasma as well as bonding strength,tensile pr... Alkali lignin was processed by plasma and then used in modification of phenol formaldehyde resin in this study.Chemical structural changes of lignin which was processed by plasma as well as bonding strength,tensile property,curing performance and thermal property of the prepared phenol formaldehyde resin which was modified by the plasma processed lignin were analyzed.Results demonstrated that:(1)Alkali lignin was degraded after the plasma processing.The original groups were destroyed,and the aromatic rings collected abundant free radicals and oxygen-containing functional groups like hydroxyls,carbonyls,carboxyls and acyls were introduced into increase the reaction activity of lignin significantly.(2)The introduction of alkali lignin decreased the free formaldehyde content and increased bonding strength and toughness of the prepared phenol formaldehyde resin,especially after the introduction of lignin treated with plasma.(3)The introduction of alkali lignin led to high curing temperature for the prepared phenol formaldehyde resin,but that was reduced by the plasma processed alkali lignin.(4)The introduction of alkali lignin could also increase thermal stability of phenol formaldehyde resin,but that was modified by plasma processed alkali lignin was better than the unprocessed lignin.Based on the results,the plasma processed lignin was used to modify phenol formaldehyde resin,which could increase the strength and toughness of phenol formaldehyde resin significantly. 展开更多
关键词 Alkali lignin PLASMA phenol formaldehyde resin bonding performance tensile property
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Effect of Ethanol on Synthesis and Electrochemical Property of Mesoporous Al-doped Titanium Dioxide via Solid-state Reaction 被引量:1
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作者 LIU Shaoyou LU Jianping +1 位作者 FENG Qingge TANG Wcnhua 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2011年第4期674-681,共8页
Mesoporous aluminum-doped titanium dioxide(Al-TiO2) materials with high specific surface areas were prepared via a solid-state reaction route.The properties of these materials were characterized by X-ray diffraction(X... Mesoporous aluminum-doped titanium dioxide(Al-TiO2) materials with high specific surface areas were prepared via a solid-state reaction route.The properties of these materials were characterized by X-ray diffraction(XRD),high resolution transmission electron microscopy(HRTEM),energy dispersive spectroscopy(EDS),N2 absorption-desorption,ultraviolet visible light spectroscopy(UV-Vis) and electrochemical spectroscopy.The results show that the mesoporous structure of the product with ethanol is composed of anatase laced crystal walls with amorphous grain boundaries formed gradually by degradation.Compared with those without ethanol,these samples possess larger crystallite size since ethanol decreases the pore size at higher temperature.With the increase of ethanol amount,however,the crystallite size will grow.The amorphous grain boundaries in the mesoporous material,with a large impedance and low incidental cyclic potential,are difficult to effectively degrade and the phase transformation temperature is changed from 500 to 550℃.The growth rate of Al-TiO2 crystallites that obeys the quadratic polynomial equation may be controlled. 展开更多
关键词 mesoporous material Al-doped TiO 2 solid-state reaction ETHANOL electrochemical property
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Analysis and Dynamic Prediction of Ecological Environment Development Capacity of Qingshui River Basin 被引量:1
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作者 Rongmin XU 《Asian Agricultural Research》 2018年第5期44-47,共4页
The Ecological Footprint and Development Capacity Model were used to analyze the ecological environment development capability of the Qingshui River Basin from 2000 to 2015. On this basis,the ecological environment de... The Ecological Footprint and Development Capacity Model were used to analyze the ecological environment development capability of the Qingshui River Basin from 2000 to 2015. On this basis,the ecological environment development capacity of the Qingshui River Basin from 2016 to 2020 was dynamically predicted using the GM( 1,1) model. The results showed that the Qingshui River Basin has a strong capacity for sustainable development of the ecological environment,but it is increasingly stressed by the ecological carrying capacity. The potential unsustainability of the ecological environment is facing severe challenges. In the next 5 years,the development capacity of the ecological environment will show a growth trend,but the increase is not large,reflecting the limited development potential. Its capacity for sustainable development needs to be improved. 展开更多
关键词 EF model DC model GM(1 1) Qingshui River Basin
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The Global and Pullback Attractors for a Strongly Damped Wave Equation with Delays 被引量:2
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作者 Guoguang Lin Fangfang Xia Guigui Xu 《International Journal of Modern Nonlinear Theory and Application》 2013年第4期209-218,共10页
In this paper, we study the global and pullback attractors for a strongly damped wave equation with delays when the force term belongs to different space. The results following from the solution generate a compact set.
关键词 STRONGLY DAMPED PULLBACK ATTRACTOR GLOBAL ATTRACTOR DELAYS
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