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Preparation of Film Based on Polyvinyl Alcohol Modified by Alkaline Starch and Lignin Fiber
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作者 yunxia zhou Hisham Essawy +5 位作者 Ai Liu Chenyu Yang Defa Hou Xiaojian zhou Guanben Du Jun Zhang 《Journal of Renewable Materials》 SCIE EI 2023年第2期837-852,共16页
This study presents an easily prepared film based on alkaline starch-polyvinyl alcohol hybrid and lignin fiber as an additive(SPL film).The SPL film was prepared under acidic conditions through a polycondensation reac... This study presents an easily prepared film based on alkaline starch-polyvinyl alcohol hybrid and lignin fiber as an additive(SPL film).The SPL film was prepared under acidic conditions through a polycondensation reaction of PVA and a mixture incorporating alkaline starch and lignin fiber from agriculture or forest source.The examination using scanning electron microscopy(SEM)showed that the surface of SPL film was smooth and the lignin fiber had good compatibility within the film hybrid.Electrospray ionization mass spectroscopy(ESI-MS)and fourier transform infrared(FTIR)investigations indicated that alkaline starch and lignin fiber reacted with PVA under acidic conditions and that–CH_(2)–O–groups were involved in the cross-linking of the SPL system.In addition,the SPL film exhibited only 4%light transmittance,which effectively reduces the ultraviolet and visible light(UV-Vis)penetration,along with good performance when exposed to thermal degradation,in which the mass loss reached around 60%at 400℃.More-over,the SPL film acquired excellent tensile strength,which is much higher than that of PVA-lignin(PL)composite film. 展开更多
关键词 Bio-based film STARCH lignin fiber polyvinyl alcohol tensile strength
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Formaldehyde Free Renewable Thermosetting Foam Based on Biomass Tannin with a Lignin Additive 被引量:1
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作者 Bowen Liu yunxia zhou +6 位作者 Hisham Essawy Shang Feng Xuehui Li Jingjing Liao Xiaojian zhou Jun Zhang Sida Xie 《Journal of Renewable Materials》 SCIE EI 2022年第11期3009-3024,共16页
This study presents easily prepared free formaldehyde bio-based foam based on a prepared thermosetting resin comprising tannin–lignin–furfuryl alcohol-glyoxal(TLFG)via mechanical stirring in presence of ether as a f... This study presents easily prepared free formaldehyde bio-based foam based on a prepared thermosetting resin comprising tannin–lignin–furfuryl alcohol-glyoxal(TLFG)via mechanical stirring in presence of ether as a foaming agent.The foam was developed through a co-polycondensation reaction of glyoxal and furfuryl alcohol with condensed tannin and lignin,which is a forest-derived product.Investigation using scanning electron microscopy(SEM)showed more closed-cell structure without cracks and collapse in the TLFG foam,with a higher apparent density with respect to tannin–furanic–formaldehyde(TFF)foam.Differential scanning calorimetry(DSC),dynamic thermomechanical analysis(DTMA),and thermogravimetric analysis(TGA)investigations revealed that the curing process of TLFG foam proceeds easily even at a lower temperature.Additionally,it acquired higher heat resistance than TFF foam.Moreover,TLFG has a more robust chemical network structure,which contributes efficiently to the mechanical strength and a lower pulverization degree compared with TFF-derived foam.Fourier transform infrared spectrometry(FTIR)and electrospray ionization mass spectrometry(ESI-MS)proved that the cross-inking reactions between tannin,lignin,furfuryl alcohol,and glyoxal have been proceeded efficiently. 展开更多
关键词 Foam materials heat resistance TANNIN LIGNIN GLYOXAL compressive strength
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On-Line Scheduling for Jobs with Arbitrary Release Times on Parallel Related Uniform Machines 被引量:1
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作者 Xiayan Cheng Rongheng Li yunxia zhou 《Intelligent Information Management》 2016年第4期98-102,共5页
A parallel related uniform machine system consists of m machines with different processing speeds. The speed of any machine is independent on jobs. In this paper, we consider online scheduling for jobs with arbitrary ... A parallel related uniform machine system consists of m machines with different processing speeds. The speed of any machine is independent on jobs. In this paper, we consider online scheduling for jobs with arbitrary release times on the parallel uniform machine system. The jobs appear over list in terms of order. An order includes the processing size and releasing time of a job. For this model, an algorithm with competitive ratio of 12 is addressed in this paper. 展开更多
关键词 Online Scheduling Uniform Machine Competitive Ratio Approximation Algorithm
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Preparation of an Abrasive Grinding Wheel Based on Tannin Resin Cross- Linked by Furfuryl Alcohol, Urea and Glyoxal
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作者 Jinxing Li Jun Zhang +4 位作者 yunxia zhou Zhaoling zhou Hisham Essawy Xiaojian zhou Guanben Du 《Journal of Renewable Materials》 SCIE EI 2020年第9期1019-1032,共14页
Simple bio-based abrasive grinding wheel based on thermosetting resin matrix was developed starting with condensed tannin and furfuryl alcohol,which are mainly derived from forest and agricultural products like tree b... Simple bio-based abrasive grinding wheel based on thermosetting resin matrix was developed starting with condensed tannin and furfuryl alcohol,which are mainly derived from forest and agricultural products like tree barks,wheat and crops.Fourier transform infrared spectra(FTIR)signified the acidic conditions are quiet efficient for the reaction of furfuryl alcohol,urea and glyoxal all together and the-CH_(2)-NH-and-CH_(2)-O-CH(OH)-groups are predominating in cross-linking of the tannin-furfuryl alcohol-urea-glyoxal(TFUG)resin.The strengthening contribution of the tannin was also confirmed by the preservation of its distinct crystallinity using X-ray diffraction(XRD).Differential scanning calorimetry(DSC)and thermogravimetric analysis(TGA)ensured that TFUG resin can be cured at low temperature and offer higher heat resistance compared with phenol-formaldehyde(PF)resin.The high hardness and excellent compressive strength revealed by the corresponding investigations such as Brinell hardness,compression resistance,and grinding tests suggested a strong abrasive ability using the new grinding wheel compared with lab-made grinding wheel based on PF resin.This could be ascribed to the absence of cracks and low content of formed holes as confirmed using scanning electron microscopy(SEM)and balanced reaction conditions that leads to network structure with regular local reinforcements and homogeneous crosslink density. 展开更多
关键词 TANNIN furfuryl alcohol bio-based resin grinding wheel
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<i>LPT</i>Algorithm for Jobs with Similar Sizes on Three Machines
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作者 Yajie Ma Rongheng Li yunxia zhou 《Applied Mathematics》 2019年第11期947-955,共9页
In this paper, LPT (largest processing time) algorithm is considered for scheduling jobs with similar sizes on three machines. The objective function is to minimize the maximum completion time of all machines. The wor... In this paper, LPT (largest processing time) algorithm is considered for scheduling jobs with similar sizes on three machines. The objective function is to minimize the maximum completion time of all machines. The worst case performance ratio of the LPT algorithm is given as a piecewise linear function of r if job sizes fall in [1, r]. Our result is better than the existing result. Furthermore, the ratio given here is the best. That means our result cannot be improved any more. 展开更多
关键词 LPT ALGORITHM Parallel Machine Performance Ratio SCHEDULE
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Archaea Diversity of Five Hot Springs in Lushan from Henan
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作者 Ke ZHANG Li LIU +8 位作者 Xuyang ZHANG Shufang ZHANG Xinhua ZHENG Yu WANG Junfeng ZHANG Bingjie LI yunxia zhou Fuan WANG Xichao XIA 《Meteorological and Environmental Research》 CAS 2020年第1期48-52,共5页
There are five hot springs named separately SHANGT,ZHONGT,WENT,XIAT and SHENT in Lushan County,Pingdingshan City,Henan Province.The archaeal diversity of the five hot springs was investigated and analyzed.16 S rD NA v... There are five hot springs named separately SHANGT,ZHONGT,WENT,XIAT and SHENT in Lushan County,Pingdingshan City,Henan Province.The archaeal diversity of the five hot springs was investigated and analyzed.16 S rD NA v4-5 genes of archaea were sequenced by Illumina Hisiq2500 PE250 technology.The numbers of sample sequences and OTUs were sorted by using Uparse,Mothur,SILVA,MUSCLE and Qiime software.Finally,the archaeal abundance and diversity in the five hot springs were analyzed.87993,67326,44400,48611 and 48495 effective reads have been obtained from SHANGT,ZHONGT,WENT,XIAT and SHENT respectively,and 520,280,678,451 and 437 OTUs have been acquired.The analysis of archaeal classification showed that the archaea from the five hot springs could be classified into 11 phyla,in which Thaumarchaeota accounted for 95.25%and was the dominant archaea.In the genera level,the dominant archaea of the SHANGT,ZHONGT and WENT was Candidatus-Nitrosocaldus,and unidentified-Thaumarchaeota was the dominant archaea in XIAT and SHENT.The results showed that the five hot springs in Lushan are rich in microbial resources.The research provided basic data for further research and utilization of the archaea resources in the five hot springs of Lushan. 展开更多
关键词 Hot SPRING ARCHAEA 16S RDNA GENES Hisiq2500 PE250
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Better Algorithm for Order On-Line Scheduling on Uniform Machines
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作者 Rongheng Li yunxia zhou 《International Journal of Intelligence Science》 2019年第2期59-65,共7页
In this paper, we consider online scheduling for jobs with arbitrary release times on the parallel uniform machine system. An algorithm with competitive ratio of 7.4641 is addressed, which is better than the best exis... In this paper, we consider online scheduling for jobs with arbitrary release times on the parallel uniform machine system. An algorithm with competitive ratio of 7.4641 is addressed, which is better than the best existing result of 12. 展开更多
关键词 Online SCHEDULING UNIFORM Machine COMPETITIVE RATIO LS ALGORITHM
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Ordinal Semi On-Line Scheduling for Jobs with Arbitrary Release Times on Identical Parallel Machines
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作者 Sai Ji Rongheng Li yunxia zhou 《Intelligent Information Management》 2017年第6期245-254,共10页
In this paper, we investigate the problem of semi-on-line scheduling n jobs on m identical parallel machines under the assumption that the ordering of the jobs by processing time is known and the jobs have arbitrary r... In this paper, we investigate the problem of semi-on-line scheduling n jobs on m identical parallel machines under the assumption that the ordering of the jobs by processing time is known and the jobs have arbitrary release times. Our aim is to minimize the maximum completion time. An ordinal algorithm is investigated and its worst case ratio is analyzed. 展开更多
关键词 SCHEDULE Algorithm Worst Case Ratio Parallel MACHINES
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Better Algorithm of Ordinal Online Schedule for Jobs with Similar Sizes on Two Machines
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作者 Limin Wang Rongheng Li yunxia zhou 《American Journal of Operations Research》 2019年第5期235-243,共9页
Ordinal online schedule for jobs with similar sizes in on two parallel machines system is considered. Firstly it is proved that the worst case performance ratio of the existing algorithm P2 cannot be improved even if ... Ordinal online schedule for jobs with similar sizes in on two parallel machines system is considered. Firstly it is proved that the worst case performance ratio of the existing algorithm P2 cannot be improved even if the job processing times are known in for any . Then a better algorithm named S is developed and its worst case performance ratio is given for? . 展开更多
关键词 SEMI-ONLINE Scheduling Pm ALGORITHM S ALGORITHM Worst Performance Ratio
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