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生成式人工智能赋能本科生科研能力培养——ChatGPT支持的CUREs教学模式
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作者 吴忭 李凤鸣 胡艺龄 《现代远程教育研究》 CSSCI 北大核心 2024年第3期3-10,28,共9页
为促进高等教育中高素质创新人才培养,构建以学生为中心的科研训练与课程教学整合模式是有效途径。当前基于课程的本科生科研体验(CUREs)教学模式虽在增强学生对科学本质的理解等方面具有一定优势,但在激发学生研究动机方面存在一些不... 为促进高等教育中高素质创新人才培养,构建以学生为中心的科研训练与课程教学整合模式是有效途径。当前基于课程的本科生科研体验(CUREs)教学模式虽在增强学生对科学本质的理解等方面具有一定优势,但在激发学生研究动机方面存在一些不足。将支持高效反馈的生成式人工智能ChatGPT引入人机协作研究过程中,有助于改善学生的科研体验,推动科研项目化学习。通过对ChatGPT支持的CUREs教学模式的设计与实施,发现该模式有助于培养学生的科研能力,提升他们的科研知识水平、科研技能水平和科研情感水平。尽管学生认同该教学模式的有效性和易用性,但其实际效果的发挥仍需人类智慧的参与。未来需要持续升级和优化生成式人工智能技术,确保技术应用高效且符合伦理标准;应用生成式人工智能技术重构教学模式,并通过长周期、跨场域实践检验其应用效果;强调人工智能与人类智慧的互补协作,真正实现生成式人工智能赋能学生科研能力提升。 展开更多
关键词 生成式人工智能 ChatGPT 科研能力 CUREs 教学模式
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Fabrication and Properties of a New Reactive Diluent for Cationic UV Curing
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作者 吴正森 黄笔武 +1 位作者 LIU Yuansheng SHEN Han 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第4期1053-1060,共8页
The reactive diluent prepared by siloxane modified Trimethylene oxide can improve the performance of the UV curing system.Therefore,1,7-bis[(3-ethyl-3-methoxyoxacylobutane)propyl]octadecylosiloxane(BEMOPOMTS)was synth... The reactive diluent prepared by siloxane modified Trimethylene oxide can improve the performance of the UV curing system.Therefore,1,7-bis[(3-ethyl-3-methoxyoxacylobutane)propyl]octadecylosiloxane(BEMOPOMTS)was synthesized from diethyl carbonate,trimethylopropanes,allyl bromide,and 1,1,3,3,5,5,7,7-octadecylosiloxane as the main raw materials.BEMOPOMTS can be used as reactive diluents in the field of cationic UV curing.It has good thermal stability,and the addition of BEMOPOMTS significantly improves the tensile strength and elongation at break of epoxy resin.Compared with the pure epoxy resin,adding 20%BEMOPOMTS increased the elastic modulus by 25%to 677 MPa. 展开更多
关键词 UV curing cation curing reactive diluent SILOXANE
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Experimental investigation of vibration pretreatment-microwave curing process for carbon fiber reinforced resin matrix composites
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作者 ZHANG De-chao ZHAN Li-hua +4 位作者 MA Bo-lin YAO Shun-ming GUO Jin-zhan GUAN Cheng-long LIU Shu 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第6期1838-1855,共18页
The vibration pretreatment-microwave curing process is an efficient,low energy consumption,and high-quality out-of-autoclave curing process for carbon fiber resin matrix composites.This study aims to investigate the i... The vibration pretreatment-microwave curing process is an efficient,low energy consumption,and high-quality out-of-autoclave curing process for carbon fiber resin matrix composites.This study aims to investigate the impact of vibration pretreatment temperature on the fiber weight content,microscopic morphology and mechanical properties of the composite laminates by using optical digital microscopy,universal tensile testing machine and thermo-gravimetric analyzer.Additionally,the combined mode of Bragg fiber grating sensor and temperature measurement fiber was employed to explore the effect of vibration pretreatment on the strain process during microwave curing.The study results revealed that the change in vibration pretreatment temperature had a slight impact on the fiber weight content when the vibration acceleration remained constant.The metallographic and interlaminar strength of the specimen formed at a vibration pretreatment temperature of 80℃ demonstrated a porosity of 0.414% and a 10.69% decrease in interlaminar shear strength compared to autoclave curing.Moreover,the introduction of the vibration energy field during the microwave curing process led to a significant reduction in residual strain in both the 0°and 90°fiber directions,when the laminate was cooled to 60℃. 展开更多
关键词 VIBRATION microwave curing POROSITY interlaminar shear strength thermo-gravimetric analysis curing strain
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基于改进CURE聚类的运营商用户云数据挖掘方法 被引量:1
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作者 雷中锋 徐秀 +3 位作者 张艳菲 曲延庆 宋强 刘良 《电脑编程技巧与维护》 2024年第4期62-64,共3页
为了优化运营商用户云数据挖掘效果、提升数据挖掘质量,开展基于改进CURE聚类的运营商用户云数据挖掘方法研究。首先,确定运营商用户云数据来源,采集与预处理运营商用户云数据。其次,设计数据挖掘关联规则,得出不同用户云数据之间的关... 为了优化运营商用户云数据挖掘效果、提升数据挖掘质量,开展基于改进CURE聚类的运营商用户云数据挖掘方法研究。首先,确定运营商用户云数据来源,采集与预处理运营商用户云数据。其次,设计数据挖掘关联规则,得出不同用户云数据之间的关联性。最后,利用改进CURE聚类算法,设计运营商用户云数据挖掘流程,输出聚类结果作为数据挖掘结果,并建立数据仓库,集中存储和管理用户云数据挖掘结果。实验结果表明,运用提出的方法,数据挖掘轮廓系数更接近1,聚类合理,挖掘效果优势显著,应用效果较好。 展开更多
关键词 改进CURE聚类 运营商 用户 云数据 挖掘
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Alkali Tolerance of Concrete Internal Curing Agent Based on Sodium Carboxymethyl Starch
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作者 陈梅花 刘荣进 +3 位作者 CHEN Ping JING Daiyan WAN Dandan FU Siyuan 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第1期82-90,共9页
Internal curing agents (ICA) based on super absorbent polymer have poor alkali tolerance and reduce the early strength of concrete.An alkali tolerate internal curing agent (CAA-ICA) was designed and prepared by using ... Internal curing agents (ICA) based on super absorbent polymer have poor alkali tolerance and reduce the early strength of concrete.An alkali tolerate internal curing agent (CAA-ICA) was designed and prepared by using sodium carboxymethyl starch (CMS) with high hydrophilicity,acrylic acid (AA) containing anionic carboxylic group and acrylamide (AM) containing non-ionic amide group as the main raw materials.The results show that the ratio of CAA-ICA alkali absorption solution is higher than that existing ICA,which solves the low water absorption ratio of the ICA in alkali environment.The water absorption ratio of CAA-ICA in saturated Ca(OH)_(2) solution is 95.8 g·g^(-1),and the alkali tolerance coefficient is 3.4.The application of CAA-ICA in cement-based materials can increase the internal relative humidity and miniaturize the pore structure.The compressive strength of mortar increases up to 12.95%at 28 d,which provids a solution to overcome the reduction of the early strength. 展开更多
关键词 alkali tolerance sodium carboxymethyl starch internal curing agent compressive strength
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Fluorinated semi-interpenetrating polymer networks for enhancing the mechanical performance and storage stability of polymer-bonded explosives by controlling curing and phase separation rates
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作者 Chao Deng Huihui Liu +1 位作者 Yongping Bai Zhen Hu 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第8期58-66,共9页
Herein, the effect of fluoropolymer binders on the properties of polymer-bonded explosives(PBXs) was comprehensively investigated. To this end, fluorinated semi-interpenetrating polymer networks(semiIPNs) were prepare... Herein, the effect of fluoropolymer binders on the properties of polymer-bonded explosives(PBXs) was comprehensively investigated. To this end, fluorinated semi-interpenetrating polymer networks(semiIPNs) were prepared using different catalyst amounts(denoted as F23-CLF-30-D). The involved curing and phase separation processes were monitored using Fourier-transform infrared spectroscopy, differential scanning calorimetry, a haze meter and a rheometer. Curing rate constant and activation energy were calculated using a theoretical model and numerical method, respectively. Results revealed that owing to its co-continuous micro-phase separation structure, the F23-CLF-30-D3 semi-IPN exhibited considerably higher tensile strength and elongation at break than pure fluororubber F2314 and the F23-CLF-30-D0 semi-IPN because the phase separation and curing rates matched in the initial stage of curing.An arc Brazilian test revealed that F23-CLF-30-D-based composites used as mock materials for PBXs exhibited excellent mechanical performance and storage stability. Thus, the matched curing and phase separation rates play a crucial role during the fabrication of high-performance semi-IPNs;these factors can be feasibly controlled using an appropriate catalyst amount. 展开更多
关键词 Semi-interpenetrating polymer networks FLUOROPOLYMER curing rate Phase separation rate Polymer-bonded explosives
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The Influence of CO_(2) Cured Manganese Slag on the Performance and Mechanical Properties of Ultra-High Performance Concrete
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作者 Ligai Bai Guihua Yang 《Fluid Dynamics & Materials Processing》 EI 2024年第8期1717-1730,共14页
The presence of toxic elements in manganese slag(MSG)poses a threat to the environment due to potential pollution.Utilizing CO_(2) curing on MS offers a promising approach to immobilize toxic substances within this ma... The presence of toxic elements in manganese slag(MSG)poses a threat to the environment due to potential pollution.Utilizing CO_(2) curing on MS offers a promising approach to immobilize toxic substances within this material,thereby mitigating their release into the natural surroundings.This study investigates the impact of CO_(2) cured MS on various rheological parameters,including slump flow,plastic viscosity(η),and yield shear stress(τ).Additionally,it assesses flexural and compressive strengths(f_(t) and f_(cu)),drying shrinkage rates(DSR),durability indicators(chloride ion migration coefficient(CMC),carbonization depth(CD)),and the leaching behavior of heavy metal elements.Microscopic examination via scanning electron microscopy(SEM)is employed to elucidate the underlying mechanisms.The results indicate that CO_(2) curing significantly enhances the slump flow of ultra-high performance concrete(UHPC)by up to 51.2%.Moreover,it reduces UHPC’sηandτby rates ranging from 0%to 52.7%and 0%to 40.2%,respectively.The DSR exhibits a linear increase corresponding to the mass ratio of CO_(2) cured MS.Furthermore,CO_(2) curing enhances both f_(t) and f_(cu) of UHPC by up to 28.7%and 17.6%,respectively.The electrical resistance is also improved,showing an increase of up to 53.7%.The relationship between mechanical strengths and electrical resistance follows a cubic relationship.The CO_(2) cured MS demonstrates a notable decrease in the CMC and CD by rates ranging from 0%to 52.6%and 0%to 26.1%,respectively.The reductions of leached chromium(Cr)and manganese(Mn)are up to 576.3%and 1312.7%,respectively.Overall,CO_(2) curing also enhances the compactness of UHPC,thereby demonstrating its potential to improve both mechanical and durability properties. 展开更多
关键词 CO_(2)curing manganese slag steel fibers mechanical strengths salt action
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Functional cure of chronic hepatitis B-hope or hype?
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作者 Gautam Ray 《World Journal of Hepatology》 2024年第9期1199-1205,共7页
Chronic hepatitis B constitutes a substantial disease burden worldwide.The steps advocated by the World Health Organization in 2016 to eradicate hepatitis B by 2030 has failed to achieve significant progress,especiall... Chronic hepatitis B constitutes a substantial disease burden worldwide.The steps advocated by the World Health Organization in 2016 to eradicate hepatitis B by 2030 has failed to achieve significant progress,especially with respect to immu-nization coverage and linkage to care.The lack of governmental and public awar-eness regarding the long-term implications of hepatitis B burden cause under-funding of developmental projects.The presently approved treatment modalities have limited efficacy in complete viral eradication,hence the need for newer molecules to achieve functional cure(sustained undetectable hepatitis B surface antigen(HBsAg)and hepatitis B virus DNA in peripheral blood after a finite period of therapy).However,preliminary results from trials of novel therapies show their inadequacy to achieve this end by themselves but better performance with a low baseline serum HBsAg with nucleos(t)ide analogues(NA)treatment which need to be combined with/without pegylated interferon as an immu-nomodulator.Such therapy is limited by cost and adverse events and need to show incremental benefit over the standard of care(long-term NA therapy)with respect to efficacy and drug toxicities,making the development process tenuous.Thus,while such therapies continue to be tested,strategies should still focus on prevention of transmission by non-pharmaceutical measures,vaccination and increasing linkage to care. 展开更多
关键词 Hepatitis B DRUGS Clinical trial THERAPY Novel therapies Functional cure
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Study on Effects of Curing Process on Characteristics of Marinated Beef Products
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作者 Bo HOU Jiamin ZHANG +2 位作者 Wei WANG Ting BAI Lili JI 《Agricultural Biotechnology》 2024年第3期64-68,74,共6页
[Objectives]This study was conducted to compare the effects of different curing processes on the characteristics of marinated beef.[Methods]Marinated beef was obtained by two curing processes:static curing and injecti... [Objectives]This study was conducted to compare the effects of different curing processes on the characteristics of marinated beef.[Methods]Marinated beef was obtained by two curing processes:static curing and injection and vacuum tumbling curing.The effects of the two curing processes on the production rate,curing absorption rate,water content,soluble protein content,amino acid nitrogen content,texture characteristics and microstructure of the product were compared.[Results]Compared with static curing,the production rate of marinated beef increased by 10%,the curing absorption rate increased by 28%,the texture and microstructure were improved,and the water content increased,while the soluble protein content decreased.As a result,the sensory score was higher.There was no significant difference in the content of amino acid nitrogen,but it decreased compared with raw meat.To sum up,injection and vacuum tumbling curing is more conducive to the processing of marinated beef.[Conclusions]This study provides a theoretical basis for the industrial production of marinated beef,and lays a foundation for in-depth exploration of injection and vacuum tumbling curing technique of marinated beef. 展开更多
关键词 Marinated beef curing process MICROSTRUCTURE TEXTURE Brine injection
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Hepatitis B cure:Current situation and prospects
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作者 Ya-Ping Li Chen-Rui Liu +1 位作者 Ling He Shuang-Suo Dang 《World Journal of Hepatology》 2024年第6期900-911,共12页
Achievement of a‘clinical cure’in chronic hepatitis B(CHB)implies sustained virological suppression and immunological control over the infection,which is the ideal treatment goal according to domestic and internatio... Achievement of a‘clinical cure’in chronic hepatitis B(CHB)implies sustained virological suppression and immunological control over the infection,which is the ideal treatment goal according to domestic and international CHB management guidelines.Clinical practice has shown encouraging results for specific patient cohorts using tailored treatment regimens.These regimens incorporate either nucleos(t)ide analogs,immunomodulatory agents such as pegylated interferonα,or a strategic combination of both,sequentially or concurrently administered.Despite these advancements in the clinical handling of hepatitis B,achieving a clinical cure remains elusive for a considerable subset of patients due to the number of challenges that preclude the realization of optimal treatment outcomes.These include,but are not limited to,the emergence of antiviral resistance,incomplete immune recovery,and the persistence of covalently closed circular DNA.Moreover,the variance in response to interferon therapy and the lack of definitive biomarkers for treatment cessation also contribute to the complexity of achieving a clinical cure.This article briefly overviews the current research progress and existing issues in pursuing a clinical cure for hepatitis B. 展开更多
关键词 Chronic hepatitis B Clinical cure Polyethylene glycol interferon Treatment strategies Research progress
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Modelling the Survival of Western Honey Bee Apis mellifera and the African Stingless Bee Meliponula ferruginea Using Semiparametric Marginal Proportional Hazards Mixture Cure Model
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作者 Patience Isiaho Daisy Salifu +1 位作者 Samuel Mwalili Henri E. Z. Tonnang 《Journal of Data Analysis and Information Processing》 2024年第1期24-39,共16页
Classical survival analysis assumes all subjects will experience the event of interest, but in some cases, a portion of the population may never encounter the event. These survival methods further assume independent s... Classical survival analysis assumes all subjects will experience the event of interest, but in some cases, a portion of the population may never encounter the event. These survival methods further assume independent survival times, which is not valid for honey bees, which live in nests. The study introduces a semi-parametric marginal proportional hazards mixture cure (PHMC) model with exchangeable correlation structure, using generalized estimating equations for survival data analysis. The model was tested on clustered right-censored bees survival data with a cured fraction, where two bee species were subjected to different entomopathogens to test the effect of the entomopathogens on the survival of the bee species. The Expectation-Solution algorithm is used to estimate the parameters. The study notes a weak positive association between cure statuses (ρ1=0.0007) and survival times for uncured bees (ρ2=0.0890), emphasizing their importance. The odds of being uncured for A. mellifera is higher than the odds for species M. ferruginea. The bee species, A. mellifera are more susceptible to entomopathogens icipe 7, icipe 20, and icipe 69. The Cox-Snell residuals show that the proposed semiparametric PH model generally fits the data well as compared to model that assume independent correlation structure. Thus, the semi parametric marginal proportional hazards mixture cure is parsimonious model for correlated bees survival data. 展开更多
关键词 Mixture Cure Models Clustered Survival Data Correlation Structure Cox-Snell Residuals EM Algorithm Expectation-Solution Algorithm
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Securing the Sea Lanes
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作者 MAHASHA RAMPEDI 《ChinAfrica》 2024年第2期34-34,共1页
Some people,mainly in the West,were taken by surprise when six Chinese warships were seen near the Red Sea in October 2023 amid the conflict in Gaza.Some Western media and politicians tried to frame China’s mission a... Some people,mainly in the West,were taken by surprise when six Chinese warships were seen near the Red Sea in October 2023 amid the conflict in Gaza.Some Western media and politicians tried to frame China’s mission as an escalatory move in the Middle East. 展开更多
关键词 curing MIDDLE tried
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Securing Sustenance
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《ChinAfrica》 2024年第1期16-17,共2页
National food security is the backbone of any economy,and achieving food security is essential for the prosperity of a nation.During my study in China at the Institute of South-South Cooperation and Development,Peking... National food security is the backbone of any economy,and achieving food security is essential for the prosperity of a nation.During my study in China at the Institute of South-South Cooperation and Development,Peking University,from September 2022 to July 2023,I leant how China has managed to achieve food security despite its large population of around 1.4 billion and numerous other challenges by means of strategic planning,e"ective policy execution,technological advancement and global collaboration. 展开更多
关键词 BACKBONE POLICY curing
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Synthesis of Ionic and Non-Ionic Modified Waterborne Polyurethane Curing Agent
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作者 Ying Qiao Xu-dong Zhang 《Journal of Electronic Research and Application》 2024年第1期86-92,共7页
By using HDI and TMP as the main raw materials,polyethylene glycol 400(PEG400)is used as a non-ionic hydrophilic modifier,and sodium hydroxyethyl sulfonate is used as an ionic hydrophilic modifier to synthesize a dual... By using HDI and TMP as the main raw materials,polyethylene glycol 400(PEG400)is used as a non-ionic hydrophilic modifier,and sodium hydroxyethyl sulfonate is used as an ionic hydrophilic modifier to synthesize a dual hydrophilic modified polyurethane curing agent.Research revealed that introducing PEG400 for hydrophilic chain segments and sodium hydroxyethyl sulfonate for hydrophilic ionic groups in the polyurethane curing agent component leads to a uniform distribution of hydrophilic components,significantly enhancing compatibility with the aqueous polyol component,and results in excellent film performance.The synthesis process and film were characterized using Fourier transform infrared spectroscopy and high-resolution scanning electron microscopy in the study. 展开更多
关键词 COATING Water polyurethane curing agent Two-package Double modification
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Advancements and Applications of Polyurethane Curing Technology in Railway Track Bed Construction in China
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作者 Yizhe Li 《Journal of World Architecture》 2024年第1期12-17,共6页
This paper examines the application of polyurethane curing technology in the construction of railway track beds,with a specific focus on its implementation in China’s rapidly developing railway infrastructure.The stu... This paper examines the application of polyurethane curing technology in the construction of railway track beds,with a specific focus on its implementation in China’s rapidly developing railway infrastructure.The study begins by identifying the limitations of traditional ballasted track beds,especially under the demands of high-speed and heavyload railways.It then methodically analyzes the advantages of polyurethane-cured track beds,highlighting their improved mechanical properties,including enhanced stability and durability.The paper further explores the benefits of transitioning to prefabricated polyurethane track beds,emphasizing significant cost reductions,better construction quality,and enhanced maintainability.Through a detailed review of experimental data and practical applications,the paper demonstrates the efficacy of polyurethane track beds in various railway settings.A critical part of the research involves optimizing the structural parameters of polyurethane track beds to achieve the best balance of mechanical and damping properties.The conclusion of the paper underscores the potential of polyurethane curing technology as a transformative approach to railway track bed construction,offering a solution to the challenges posed by traditional methods and aligning with the evolving needs of modern railways. 展开更多
关键词 Polyurethane curing Railway track bed Infrastructure optimization Prefabricated construction
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Study on Loading Leaves Density with Cage Clamp on Quality of Cured Tobaccos in Bulk-Curing Barn
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作者 王能如 余金恒 +2 位作者 罗荣欣 林北森 尹永强 《Agricultural Science & Technology》 CAS 2014年第8期1317-1321,共5页
In order to determine the best loading density of tobacco leaf with cage clamp in bulk-curing barns, a curing test was conducted on middle-part tobacco leaves. The results showed that for good appearance quality of cu... In order to determine the best loading density of tobacco leaf with cage clamp in bulk-curing barns, a curing test was conducted on middle-part tobacco leaves. The results showed that for good appearance quality of cured tobacco, the loading density at 59.52 kg/m2 (4 000 kg/barn) was the best, fol owed by 66.96 kg/m2 (4 500 kg/barn) and 74.40 kg/m2 (5 000 kg/barn). As leaf loading density increased, the contents of leaf nicotine and total nitrogen increased, sugar content had smal changes, the ratio of sugar to nicotine decreased and tended to be balanced and the content of neutral aroma substances was decreasing, but the difference among treatments was not significant. With the increase of loading density, the sensory quality of cured leaf was better. When leaf loading density was 66.96 kg/m2 (4 500 kg/barn), apperance quality of cured leaf improved considerably, with prominent aro-ma. Therefore, the best loading density of tobacco leaf in cage clamp of bulk-curing barn would be 66.96 kg/m2 (4 500 kg/barn) . 展开更多
关键词 Flue-cured tobacco Bulk curing Tobacco quality Cage clamp Loadingleaves density
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Curing Characteristics and Suitable Harvest Maturity of Fresh Flue-cured Tobacco Leaves in Ankang Tobacco Growing Areas 被引量:2
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作者 朱峰 饶智 +3 位作者 沈始权 孙福山 任杰 肖头杰 《Agricultural Science & Technology》 CAS 2015年第4期815-819,共5页
CuItivars K326, Yunyan 87 and Guiyan 4 were used to investigate the curing characteristics and suitabIe harvest maturity of fresh fIue-cured tobacco Ieaves in Ankang tobacco growing areas. ResuIts indicated that the w... CuItivars K326, Yunyan 87 and Guiyan 4 were used to investigate the curing characteristics and suitabIe harvest maturity of fresh fIue-cured tobacco Ieaves in Ankang tobacco growing areas. ResuIts indicated that the water Ioss of K326 was sIow,and the Ieaves were resistant to curing and reIative easiIy to cure. The water Ioss of Yunyan 87 and Guiyan 4 were quick, and the Ieaves with normal resistance to curing were reIative difficuIt to cure. For Guiyan 4, the shrinkage of CM1 maturity was the Iargest. For K326 and Yunyan 87, the shrinkages of CM2 maturity were the Iargest whiIe the shrinkage of CM1 maturity was the Iowest, but the difference did not reach statistical significance. The proportion of top-middIe-grade tobacco Ieaves and average price for K326 were the highest with XM2, CM2 and BM2 maturity, and for Yunyan 87 were XM1, CM3 and BM2 maturity. For K326, Ieaves with XM2, CM2 and BM2 maturity showed the balanced chemical components and the best smoking quality. 展开更多
关键词 FIue-cured tobacco curing characteristic MATURITY Ankang City of Shaanxi Province
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Effects of Two Curing Methods on Quality of Yellow Sun-cured Tobacco 被引量:1
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作者 王毅 兰应海 +6 位作者 杨光辉 谢丽华 柴家荣 李光西 屈生彬 张晨东 钱颖颖 《Agricultural Science & Technology》 CAS 2012年第10期2097-2100,共4页
[Objective] The aim was to research effects of bamboo split curing method and steely barn curing method on quality of yellow sun-cured tobacco, providing scientific references for optimization of curing technology of ... [Objective] The aim was to research effects of bamboo split curing method and steely barn curing method on quality of yellow sun-cured tobacco, providing scientific references for optimization of curing technology of yellow sun-cured tobacco. [method] The tobaccos were divided into two groups treated with two methods and the related indices of treated tobaccos were then measured to evaluate effects of curing methods on quality of yellow sun-cured tobacco. [Result] Tobaccos treated with two methods were all dominated by reddish yellow and yellow; exterior quality differed little. In detail, total sugar and reducing sugar in an average level in three locations were all higher with method A than those with method B, but nicotine and total N were lower; comprehensive chemical components in group with method B proved more appropriate with higher K. In addition, sensory qualities of leaves in moderate and bottom locations were better with method B compared with method A; sensory quality of top leaves was better; comprehensive sensory quality of leaves treated with method B proved better. On the other hand, cost for method A was 2.82 times of method B; the area of sun-curing field was 3.27 times and manage- ment work was 1.77 times, which indicated that method B is low-cost and time-saving, which would be a guarantee of tobacco quality. [Conclusion] The research provides scientific references for rational use of tobacco resources and optimization of sun-curing technology. 展开更多
关键词 Yellow-sun-cured tobacco curing method Chemical component Sensory quality
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Effects of Different Flue-curing Barns on Aroma Quality of Upper Flue-cured Tobacco Leaves of K326 被引量:2
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作者 詹军 周芳芳 +4 位作者 徐成龙 张晓龙 王柱石 陈初 朱海滨 《Agricultural Science & Technology》 CAS 2014年第11期2014-2019,共6页
[Objective] This study was conducted to compare the aroma quality of up-per leaves of K326 flue-cured in different barns, and provide theoretical references for the development and optimization of bulk curing barn and... [Objective] This study was conducted to compare the aroma quality of up-per leaves of K326 flue-cured in different barns, and provide theoretical references for the development and optimization of bulk curing barn and the supporting tech-niques. [Method] The upper leaves of K326 were flue-cured in a commonness barn, a four-shelf bulk curing barn and a three-shelf bulk curing barn separately, and then the contents of aroma components and taste quality indices of the finished leaves were measured and compared. [Result] The contents of total aroma components, chromoplast pigment degradation products, phenylalanine aroma components and neophytadiene showed no significant differences in the leaves flue-cured in four-shelf bulk curing barn and commonness barn, but were significantly or very significantly higher than those in the leaves flue-cured in three-shelf bulk curing barn. The con-tents of carotenoid degradation products, Mail ard reaction products, cembranes aro-ma components and total aroma components (except neophytadiene) showed no significant difference among the three treatments. The results of sensory evaluation revealed that the sensory taste of the leaves flue-cured in four-shelf bulk curing barn was the best, as the finished leaves had rich, delicate aroma, comfortable and clean aftertaste. The leaves flue-cured in commonness barn was better than those flue-cured in three-shelf bulk curing barn in aroma quality, amount and aftertaste. [Conclusion] The four-shelf bulk curing barn had a large volume for tobacco leaf processing, but a similar baking environment to the commonness barn, which is conducive to the formation and accumulation of aroma components, so the finished leaves had similar appearance and quality with those flue-cured in commonness barn. The upper flue-cured leaves in three-shelf bulk curing bran had poorer quality than those flue-cured in the other two barns. 展开更多
关键词 Bulk curing barn Commonness barn Flue-cured tobacco K326 Upper leaf Aroma quality
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Cure Kinetics of DGEBA with Hyperbranched Poly(3-hydroxyphenyl) Phosphate as Curing Agent Studied by Non-isothermal DSC 被引量:6
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作者 YAO Liang DENG Jing QU Bao-jun SHI Wen-fang 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2006年第1期118-122,共5页
The cure kinetics of diglycidyl ether of bisphenol A (DGEBA) with hyperbranched poly (3-hydroxyphenyl) phosphate(HHPP) as the curing agent was investigated by means of non-isothermal differential scanning calori... The cure kinetics of diglycidyl ether of bisphenol A (DGEBA) with hyperbranched poly (3-hydroxyphenyl) phosphate(HHPP) as the curing agent was investigated by means of non-isothermal differential scanning calorimetry (DSC) at various heating rates. The results were compared with the corresponding results by using 1,3-dihydroxybenzene(DHB) as a model compound. The results show that HHPP can enhance the cure reaction of DGEBA, resulting in the decrease of the peak temperature of the curing curve as well as the decrease of the activation energy because of the flexible --P--O-- groups in the backbone of HHPP. However, both the activation energy of the cured polymer and the peak temperature of the curing curve are increased with DHB as a curing agent. The cure kinetics of the DGEBA/HHPP system was calculated by using the isoconversional method given by Malek. It was found that the two-parameter autocatalytic model(Sestak-Berggren equation) is the most adequate one to describe the cure kinetics of the studied System at various heating rates. The obtained non-isothermal DSC curves from the experimental data show the results being accordant with those theoretically calculated. 展开更多
关键词 Hyperbranched polyphosphate Cure kinetics Epoxy resin Non-isothermal DSC
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