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Constructing a stable interface on Ni-rich LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2) cathode via lactic acid-assisted engineering strategy 被引量:1
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作者 Weijian Tang Chengzhi Hu +4 位作者 AFei Li Xiaoqin Huang Zhangxian Chen Jianhui Su Weixin Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第3期412-422,I0010,共12页
Ni-rich layered oxides are potential cathode materials for next-generation high energy density Li-ion batteries due to their high capacity and low cost.However,the inherently unstable surface properties,including high... Ni-rich layered oxides are potential cathode materials for next-generation high energy density Li-ion batteries due to their high capacity and low cost.However,the inherently unstable surface properties,including high levels of residual Li compounds,dissolution of transition metal cations,and parasitic side reactions,have not been effectively addressed,leading to significant degradation in their electrochemical performance.In this study,we propose a simple and effective lactic acid-assisted interface engineering strategy to regulate the surface chemistry and properties of Ni-rich LiNi_(0.8)Co_(0.1)Mr_(0.1)O_(2) cathode.This novel surface treatment method successfully eliminates surface residual Li compounds,inhibits structural collapse,and mitigates cathode-electrolyte interface film growth.As a result,the lactic acidtreated LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2) achieved a remarkable capacity retention of 91.7% after 100 cycles at 0.5 C(25℃) and outstanding rate capability of 149.5 mA h g^(-1) at 10 C,significantly outperforming the pristine material.Furthermore,a pouch-type full cell incorporating the modified LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2) cathode demonstrates impressive long-term cycle life,retaining 81.5% of its capacity after 500 cycles at 1 C.More importantly,the thermal stability of the modified cathode is also dramatically improved.This study offers a valuable surface modification strategy for enhancing the overall performance of Ni-rich cathode materials. 展开更多
关键词 Residual Li lactic acid Surface modification Carbon coating Layered cathode Ni-rich
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Synergism of Zinc Oxide/Organoclay-Loaded Poly(lactic acid) Hybrid Nanocomposite Plasticized by Triacetin for Sustainable Active Food Packaging
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作者 Ponusa Songtipya Thummanoon Prodpran +1 位作者 Ladawan Songtipya Theerarat Sengsuk 《Journal of Renewable Materials》 EI CAS 2024年第5期951-967,共17页
The synergistic effect of organoclay(OC)and zinc oxide(ZnO)nanoparticles on the crucial properties of poly(lactic acid)(PLA)nanocompositefilms was systematically investigated herein.After their incorporation into PLA v... The synergistic effect of organoclay(OC)and zinc oxide(ZnO)nanoparticles on the crucial properties of poly(lactic acid)(PLA)nanocompositefilms was systematically investigated herein.After their incorporation into PLA via the solvent casting technique,the water vapor barrier property of the PLA/OC/ZnOfilm improved by a maximum of 86%compared to the neat PLAfilm without the deterioration of Young’s modulus or the tensile strength.Moreover,thefilm’s self-antibacterial activity against foodborne pathogens,including gram-negative(Escherichia coli,E.coli)and gram-positive(Staphylococcus aureus,S.aureus)bacteria,was enhanced by a max-imum of approximately 98–99%compared to the neat PLAfilm.Furthermore,SEM images revealed the homo-geneous dispersion of both nano-fillers in the PLA matrix.However,the thermal stability of thefilm decreased slightly after the addition of the OC and ZnO.Thefilm exhibited notable light barrier properties in the UV-Vis range.Moreover,the incorporation of a suitable biodegradable plasticizer significantly decreased the Tg and notably enhanced theflexibility of the nanocompositefilm by increasing the elongation at break approxi-mately 1.5-fold compared to that of the neat PLAfilm.This contributes to its feasibility as an active food packa-ging material. 展开更多
关键词 Poly(lactic acid)nanocomposite ORGANOCLAY zinc oxide barrier property antibacterial activity active food packaging
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Preparation of lactic acid bacteria compound starter cultures based on pasting properties and its improvement of glutinous rice flour and dough 被引量:1
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作者 Dengyu Wang Linlin Liu +4 位作者 Bing Wang Wenjian Xie Yanguo Shi Na Zhang Hongchen Fan 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第4期2090-2101,共12页
The effects of 5 lactic acid bacteria(LAB)fermentation on the pasting properties of glutinous rice flour were compared,and suitable fermentation strains were selected based on the changes of viscosity,setback value,an... The effects of 5 lactic acid bacteria(LAB)fermentation on the pasting properties of glutinous rice flour were compared,and suitable fermentation strains were selected based on the changes of viscosity,setback value,and breakdown value to prepare LAB compound starter cultures.The results revealed that Latilactobacillus sakei HSD004 and Lacticaseibacillus rhamnosus HSD005 had apparent advantages in increasing the viscosity and reducing the setback and breakdown values of glutinous rice flour.In particular,the compound starter created using the two abovementioned LAB in the ratio of 3:1 had better performance than that using a single LAB in improving the pasting properties and increasing the water and oil absorption capacity of glutinous rice flour.Moreover,the gelatinization enthalpy of the fermented samples increased significantly.For frozen glutinous rice dough stored for 28 days,the viscoelasticity of frozen dough prepared by compound starter was better than that of control dough,and the freezable water content was lower than that of control dough.These results indicate that compound LAB fermentation is a promising technology in the glutinous rice-based food processing industry,which has significance for its application. 展开更多
关键词 Glutinous rice flour Glutinous rice dough lactic acid bacteria compound starter cultures Pasting properties VISCOELASTICITY
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Synergistic effect of MXene on the flame retardancy and thermal degradation of intumescent flame retardant biodegradable poly(lactic acid)composites 被引量:9
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作者 Haowei Huang Dexuan Dong +5 位作者 Weijie Li Xinya Zhang Li Zhang Ying Chen Xinxin Sheng Xiang Lu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2020年第7期1981-1993,共13页
The effect of Ti3C2 MXene nanosheets on the intumescent flame retardant(IFR)poly(lactic acid)(PLA)composites was investigated among a series of PLA/IFR/MXene,which were prepared by melt blending 0-2.0 wt%MXene,10.0 wt... The effect of Ti3C2 MXene nanosheets on the intumescent flame retardant(IFR)poly(lactic acid)(PLA)composites was investigated among a series of PLA/IFR/MXene,which were prepared by melt blending 0-2.0 wt%MXene,10.0 wt%-12.0 wt%IFR and PLA together.The results of limiting oxygen index(LOI)and vertical burning(UL-94)discover that the combination of 0.5 wt%MXene and 11.5 wt%IFR synergistically improves the fire safety of PLA to reach UL-94 V-0 rating with LOI value of 33.0%.The PLA/IFR/MXene composites perform an obvious reduction in peak of heat release rate(HRR)in cone calorimeter tests(CCTs).Furthermore,the carbon residues after CCTs were characterized by scanning electron microscope(SEM),laser Raman spectroscopy(LRS),X-ray diffraction(XRD)and X-ray photoelectron spectroscopy(XPS).It is demonstrated that both the titanium composition of the MXene structure and the characteristics of the two-dimensional material enhance the PLA/IFR/MXene composite materials’ability to produce a dense barrier layer to resist burnout during thermal degradation. 展开更多
关键词 MXene Poly(lactic acid) Intumescent flame retardant Synergistic effect
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Efficient and selective upcycling of waste polylactic acid into acetate using nickel selenide
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作者 Bing Lan Yinfang Chen +4 位作者 Nantian Xiao Na Liu Chao Juan Chuan Xia Fan Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第10期575-584,I0012,共11页
The conversion of waste polylactic acid(PLA)plastics into high-value-added chemicals through electrochemical methods is a promising and sustainable approach.However,developing efficient and highly selective catalysts ... The conversion of waste polylactic acid(PLA)plastics into high-value-added chemicals through electrochemical methods is a promising and sustainable approach.However,developing efficient and highly selective catalysts for lactic acid oxidation reaction(LAOR)and understanding the reaction process are challenging.Here,we report the electrooxidation of waste PLA to acetate at a high current density of 100 mA cm-2 with high Faraday efficiency(~95%)and excellent stability(>100 h)over a nickel selenide nanosheet catalyst.In addition,a total Faraday efficiency of up to 190%was achieved for carboxylic acids,including acetic acid and formic acid,by coupling with the cathodic CO_(2) reduction reaction.In situ experimental results and theoretical simulations revealed that the catalytic activity center of LAOR was dynamically formed NiOOH species,and the surface-adsorbed SeO_(x) species accelerated the formation of Ni~(3+)species,thus promoting catalytic activity.The mechanism of lactic acid electrooxidation was further elucidated.Lactic acid was dehydrogenated to produce pyruvate first and then formed CH_3CO due to preferential C-C bond cleavage,resulting in the presence of acetate.This work demonstrated a sustainable method for recycling waste PLA and CO_(2) into high-value-added products. 展开更多
关键词 Waste plastic upcycling Poly(lactic acid) lactic acid electro-oxidation Acetic acid
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Blends of Poly(lactic acid) with Thermoplastic Acetylated Starch 被引量:2
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作者 ZHANG Kun-yu RAN Xiang-hai +2 位作者 ZHUANG Yu-gang YAO Bin DONG Li-song 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2009年第5期748-753,共6页
Blends of poly(lactic acid)(PLA) and thermoplastic acetylated starch(ATPS) were prepared by means of the melt mixing method. The results show that PLA and ATPS were partially miscible, which was confirmed with t... Blends of poly(lactic acid)(PLA) and thermoplastic acetylated starch(ATPS) were prepared by means of the melt mixing method. The results show that PLA and ATPS were partially miscible, which was confirmed with the measurement of Tg by dynamic mechanical analysis(DMA) and differrential scanning calorimetry(DSC). The mechanical and thermal properties of the blends were improved. With increasing the ATPS content, the elongation at break and impact strength were increased. The elongation at break increased from 5% of neat PLA to 25% of the blend PLA/ATPS40. It was found that the cold crystallization behavior of PLA changed evidently by addition of ATPS. The cold crystallization temperature(Tcc) of each of PLA/ATPS blends was found to shift to a lower temperature and the width of exothermic peak became narrow compared with that of neat PLA. The thermogravimetry analysis(TGA) results showed that the peak of derivative weight for ATPS moved to higher temperature with increasing PLA content in PLA/ATPS blends. It can be concluded that PLA could increase the thermal stability of ATPS. The rheological measurement reveals the melt elasticity and viscosity of the blends decreased with the increased concentration of ATPS, which was favorable to the processing properties of PLA. 展开更多
关键词 Poly(lactic acid Thermoplastic acetylated starch blEND
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Allergen degradation of bee pollen by lactic acid bacteria fermentation and its alleviatory effects on allergic reactions in BALB/c mice
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作者 Shuting Yin Qiangqiang Li +5 位作者 Yuxiao Tao Enning Zhou Kun Wang Wanwen Chen Xiangxin Li Liming Wu 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期349-359,共11页
Food allergy as a global health problem threatens food industry.Bee pollen(BP)is a typical food with allergenic potentials,although it performs various nutritional/pharmacological functions to humans.In this study,lac... Food allergy as a global health problem threatens food industry.Bee pollen(BP)is a typical food with allergenic potentials,although it performs various nutritional/pharmacological functions to humans.In this study,lactic acid bacteria(LAB)were used to ferment Brassica napus BP for alleviating its allergenicity.Four novel allergens(glutaredoxin,oleosin-B2,catalase and lipase)were identified with significant decreases in LAB-fermented BP(FBP)than natural BP by proteomics.Meanwhile,metabolomics analysis showed significant increases of 28 characteristic oligopeptides and amino acids in FBP versus BP,indicating the degradation of LAB on allergens.Moreover,FBP showed alleviatory effects in BALB/c mice,which relieved pathological symptoms and lowered production of allergic mediators.Microbial high-throughput sequencing analysis showed that FBP could regulate gut microbiota and metabolism to strengthen immunity,which were closely correlated with the alleviation of allergic reactivity.These findings could contribute to the development and utilization of hypoallergenic BP products. 展开更多
关键词 Alleviatory effects lactic acid bacteria fermentation Bee pollen allergen Gut microbiota Host metabolism
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Screening of glucosinolates degrading lactic acid bacteria and their utilization in rapeseed meal fermentation
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作者 Yifang Chen Chong Xie +2 位作者 Muhammad Bilal Pei Wang Runqiang Yang 《Grain & Oil Science and Technology》 CAS 2024年第3期168-176,共9页
Rapeseed meal is a promising food ingredient, but its utilization is limited by the presence of some potentially harmful ingredients, such as glucosinolates. Fermentation is a cost-effective method of detoxication but... Rapeseed meal is a promising food ingredient, but its utilization is limited by the presence of some potentially harmful ingredients, such as glucosinolates. Fermentation is a cost-effective method of detoxication but a food-grade starter culture with glucosinolates degradation capacity is required. In this study, 46 strains of lactic acid bacteria from traditional paocai brines were screened for their ability to glucosinolate degradation. The results showed that more than 50% of the strains significantly degraded glucosinolates. Two strains of Lactiplantibacillus(p7 and s7) with high capacity of glucosinolates degradation through producing enzymes were identified. Then,an optimized condition for rapeseed meal fermentation by p7 was established to degrade glucosinolates, which can achieve about 80% degradation. UPLC/Q-TOF-MS analysis showed that the degradation rate of individual glucosinolates was different and the degradation rate of gluconapin and progoitrin in rapeseed meal can reach more than 90%. Meanwhile, fermentation with p7 can improve safety of rapeseed meal by inhibiting the growth of Enterobacteriaceae and improve its nutritional properties by degrading phytic acid. The in vitro digestion experiments showed that the content of glucosinolates in rapeseed meal decreased significantly during gastric digestion. Meanwhile, fermentation with p7 can greatly improve the release of soluble protein and increase the contents of free essential amino acids, such as lysine(increased by 12 folds) and methionine(increased by 10 folds). 展开更多
关键词 Rapeseed meal GLUCOSINOLATES FERMENTATION lactic acid bacteria In vitro digestion
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Comparison of morphological and functional outcomes of mouse sciatic nerve repair with three biodegradable polymer conduits containing poly (lactic acid) 被引量:1
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作者 Fernanda Marques Pestana Rui C.C.Domingues +9 位作者 Júlia Teixeira Oliveira Daniela F.P.A.Durco Camila Oliveira Goulart Henrique Rocha Mendonca Anne Caroline Rodrigues dos Santos Natália Tavares de Campos Beatriz Theodoro da Silva Cristina Cardoso Pereira Cristiano Piacsek Borges Ana Maria Blanco Martinez 《Neural Regeneration Research》 SCIE CAS CSCD 2018年第10期1811-1819,共9页
Poly(lactic acid)(PLA)-containing nerve guidance conduits(NGCs) are currently being investigated for nerve repair as an alternative to autograft, which leads to permanent functional impairment in the territory i... Poly(lactic acid)(PLA)-containing nerve guidance conduits(NGCs) are currently being investigated for nerve repair as an alternative to autograft, which leads to permanent functional impairment in the territory innervated by the removed nerve. Combination of polymers modifies the physical properties of the conduits, altering their nerve-guidance properties. Conduits made from PLA-only or combined with other polymers have been used successfully for nerve repair, but their efficiency has not been compared. We compared the morphological and functional outcomes of peripheral nerve repair by using NGCs made of poly(lactic acid) and combined or not with polycaprolactone(PLA/PCL) or polyvinylpyrrolidone(PLA/PVP). To assess the functional recovery, we employed a mechanical hyperalgesia analysis, sciatic functional index(SFI), and electroneuromyography. The mechanical hyperalgesia analysis showed that the PLA group improved more rapidly than the PLA/PVP and PLA/PCL groups; similarly, in the electroneuromyography assay, the PLA group exhibited higher amplitude than the PLA/PCL and PLA/PVP groups. However, the SFI improvement rates did not differ among the groups. Morphologically, the PLA group showed more vascularization, while the nerve fiber regeneration did not differ among the groups. In conclusion, the PLA-only conduits were superior to the other NGCs tested for nerve repair. 展开更多
关键词 sciatic nerve tubulization biodegradable conduit poly(lactic acid regeneration
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Application of Next Generation Sequencing for Rapid Identification of Lactic Acid Bacteria
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作者 Xiaxia HOU Yunxia WANG +2 位作者 Shuhuan ZHAO Hongbing JIA Cuizhi LI 《Asian Agricultural Research》 2024年第4期27-32,共6页
The rapid identification of lactic acid bacteria,which are essential microorganisms in the food industry,is of great significance for industrial applications.The identification of lactic acid bacteria traditionally re... The rapid identification of lactic acid bacteria,which are essential microorganisms in the food industry,is of great significance for industrial applications.The identification of lactic acid bacteria traditionally relies on the isolation and identification of pure colonies.While this method is well-established and widely used,it is not without limitations.The subjective judgment inherent in the isolation and purification process introduces potential for error,and the incomplete nature of the isolation process can result in the loss of valuable information.The advent of next generation sequencing has provided a novel approach to the rapid identification of lactic acid bacteria.This technology offers several advantages,including rapidity,accuracy,high throughput,and low cost.Next generation sequencing represents a significant advancement in the field of DNA sequencing.Its ability to rapidly and accurately identify lactic acid bacteria strains in samples with insufficient information or in the presence of multiple lactic acid bacteria sets it apart as a valuable tool.The application of this technology not only circumvents the potential errors inherent in the traditional method but also provides a robust foundation for the expeditious identification of lactic acid bacteria strains and the authentication of bacterial powder in industrial applications.This paper commences with an overview of traditional and molecular biology methods for the identification of lactic acid bacteria.While each method has its own advantages,they are not without limitations in practical application.Subsequently,the paper provides an introduction of the principle,process,advantages,and disadvantages of next generation sequencing,and also details its application in strain identification and rapid identification of lactic acid bacteria.The objective of this study is to provide a comprehensive and reliable basis for the rapid identification of industrial lactic acid bacteria strains and the authenticity identification of bacterial powder. 展开更多
关键词 lactic acid BACTERIA RAPID identification NEXT generation SEQUENCING
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Antimicrobial Profile of Lactic Acid Bacteria Isolated from Vegetables and Indigenous Fermented Foods of India against Clinical Pathogens Using Microdilution Method 被引量:4
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作者 Ami PATEL Nihir SHAH +3 位作者 Padma AMBALAM J. B. PRAJAPATI Olle HOLST Asa LJUNGH 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2013年第9期759-764,共6页
In dairy and food industries lactic acid bacteria (LAB) have been used in form of starter culture that plays vital role in fermentation; as flavouring and texturizing or as preservative agents. There is increasing e... In dairy and food industries lactic acid bacteria (LAB) have been used in form of starter culture that plays vital role in fermentation; as flavouring and texturizing or as preservative agents. There is increasing evidence that lactobacilli which inhabit the gastrointestinal tract develop antimicrobial activities and participate in the host's defence system[1]. During fermentation, most of the LAB produces a number of different compounds like organic acids, hydrogen peroxide, diacetyl, acetaldehyde, carbon dioxide, polysaccharides, and proteinaceous compounds called bacteriocins or bacteriocinogenic peptides. 展开更多
关键词 Antimicrobial Profile of lactic acid Bacteria Isolated from Vegetables and Indigenous Fermented Foods of India against Clinical Pathogens Using Microdilution Method CFS
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Synthesis and Hydrophilic Performance of Poly(Lactic Acid)-Poly(Ethylene Glycol) Block Copolymers 被引量:2
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作者 Gang Xu Sihao Chen +2 位作者 Xiao Yan Chunyu Yang Zhichang Chen 《American Journal of Analytical Chemistry》 2016年第3期299-305,共7页
Lactide was synthesized using lactic acid and stannous octoate as raw material and catalyst, respectively. Poly(lactic acid)-poly(ethylene glycol) (PLA-PEG) was prepared by lactide and poly (ethylene glycol) (PEG) via... Lactide was synthesized using lactic acid and stannous octoate as raw material and catalyst, respectively. Poly(lactic acid)-poly(ethylene glycol) (PLA-PEG) was prepared by lactide and poly (ethylene glycol) (PEG) via ring-opening polymerization. The most appropriate technological conditions of synthesis of lactide were researched in the paper. The copolymers were measured by Infrared spectroscopy (IR) and <sup>1</sup>H nuclear magnetic resonance (<sup>1</sup>H NMR). The results proved that the lactide and PLA-PEG were synthesized successfully. Hydrophilic performance of the copolymer was measured by a water contact angle tester after prepared into a flat membrane. The water contact angle changed from 81.5? to 71.6?, which proved that the hydrophily of PLA-PEG was better than PLA. 展开更多
关键词 LACTIDE Poly(lactic acid)-Poly(Ethylene Glycol) (PLA-PEG) Prepare Hydrophily
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Poly(lactic acid)-starch/Expandable Graphite (PLA-starch/EG) Flame Retardant Composites 被引量:1
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作者 Mfiso Emmanuel Mngomezulu Adriaan Stephanus Luyt +1 位作者 Steve Anthony Chapple Maya Jacob John 《Journal of Renewable Materials》 SCIE 2018年第1期26-37,共12页
This work reports on the effect of commercial expandable graphite(EG)on the flammability and thermal decomposition properties of PLA-starch blend.The PLA-starch/EG composites were prepared by melt-mixing and their the... This work reports on the effect of commercial expandable graphite(EG)on the flammability and thermal decomposition properties of PLA-starch blend.The PLA-starch/EG composites were prepared by melt-mixing and their thermal stability,volatile pyrolysis products and flammability characteristics were investigated.The char residues of the composites,after combustion in a cone calorimeter,were analyzed with environmental scanning electron microscopy(ESEM).The thermal decomposition stability of the composites improved in the presence of EG.However,the char content was less than expected as per the combination of the wt%EG added into PLA-starch and the%residue of PLA-starch.The flammability performance of the PLA-starch/EG composites improved,especially at 15 wt%EG content,due to a thick and strong worm-like char structure.The peak heat release rate(PHRR)improved by 74%,the total smoke production(TSP)by 40%and the specific extinction area(SEA)by 55%.The improvements are attributed to the ability of EG to exfoliate at increased temperatures during which time three effects occurred:(i)cooling due to an endothermic exfoliation process,(ii)dilution due to release of H2O,SO2 and CO2 gases,and (iii)formation of a protective intumescent char layer.However,the CO and CO2 yields were found to be unfavorably high due to the presence of EG. 展开更多
关键词 Poly(lactic acid)-starch composites expandable graphite thermal stability flammability properties
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Improving the Compatibility of Biodegradable Poly (Lactic Acid) Toughening with Thermoplastic Polyurethane (TPU) and Compatibilized Meltblown Nonwoven 被引量:1
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作者 Md Obaidur Rahman Feichao Zhu Bin Yu 《Open Journal of Composite Materials》 2022年第1期1-15,共15页
Poly <span style="font-family:Verdana;">(</span><span style="font-family:Verdana;">Lactic Acid</span><span style="font-family:Verdana;">)</span><spa... Poly <span style="font-family:Verdana;">(</span><span style="font-family:Verdana;">Lactic Acid</span><span style="font-family:Verdana;">)</span><span style="font-family:Verdana;"> (PLA) is a biodegradable polymer which originates from natural resources such as corn</span><span style="font-family:Verdana;"> and</span><span style="font-family:Verdana;"> starch</span><span style="font-family:Verdana;">,</span><span style="font-family:;" "=""><span style="font-family:Verdana;"> offering excellent strength, biode</span><span style="font-family:Verdana;">gradability</span></span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> nevertheless its inherent brittleness and low impact resistance</span><span style="font-family:Verdana;"> properties ha</span><span style="font-family:Verdana;">ve</span><span style="font-family:Verdana;"> limited its application. On the other hand</span><span style="font-family:Verdana;">,</span><span style="font-family:;" "=""><span style="font-family:Verdana;"> Thermoplastic Polyu</span><span style="font-family:Verdana;">rethane (TPU) has high toughness, durability and flexibility</span></span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> which </span><span style="font-family:Verdana;">is</span><span style="font-family:Verdana;"> one of</span><span style="font-family:;" "=""><span style="font-family:Verdana;"> the </span><span style="font-family:Verdana;">most potential alternatives for enhancing the flexibility and mechanical</span><span style="font-family:Verdana;"> strength of Poly </span></span><span style="font-family:Verdana;">(</span><span style="font-family:Verdana;">Lactic Acid</span><span style="font-family:Verdana;">)</span><span style="font-family:;" "=""><span style="font-family:Verdana;"> (PLA) by blending it with a compati</span><span style="font-family:Verdana;">bilizer. With the aim to improve the mechanical and thermal properties of</span><span style="font-family:Verdana;"> Poly </span></span><span style="font-family:Verdana;">(</span><span style="font-family:Verdana;">Lactic Acid</span><span style="font-family:Verdana;">)</span><span style="font-family:;" "=""><span style="font-family:Verdana;"> (PLA) </span><span style="font-family:Verdana;">meltblown nonwovens, The Thermoplastic Polyurethane (TPU) was melt</span><span style="font-family:Verdana;"> blend</span></span><span style="font-family:Verdana;">ed with Poly </span><span style="font-family:Verdana;">(</span><span style="font-family:Verdana;">Lactic Acid</span><span style="font-family:Verdana;">)</span><span style="font-family:Verdana;"> (PLA) at the different corresponding proportions for toughening the Poly </span><span style="font-family:Verdana;">(</span><span style="font-family:Verdana;">Lactic Acid</span><span style="font-family:Verdana;">)</span><span style="font-family:Verdana;"> and the corresponding PLA/TPU MBs (meltblown nonwovens) were also manufactured. Joncryl ADR 4400 </span><span style="font-family:Verdana;">is</span><span style="font-family:Verdana;"> mixed </span><span style="font-family:Verdana;">in</span><span style="font-family:Verdana;">to the PLA matrix during processing. It was found that Joncryl had </span><span style="font-family:Verdana;">a </span><span style="font-family:;" "=""><span style="font-family:Verdana;">much higher chain extension that substantially in</span><span style="font-family:Verdana;">creased the molecular weight of the PLA matrix. SEM study revealed that Joncryl ADR 4400 is a good compatibi</span><span style="font-family:Verdana;">lizer</span></span><span style="font-family:Verdana;">.</span><span style="font-family:Verdana;"> Moreover, in this study</span><span style="font-family:Verdana;">,</span><span style="font-family:;" "=""><span style="font-family:Verdana;"> the crystallization, thermal and rheological behaviors </span><span style="font-family:Verdana;">of the corresponding PLA and TPU blends were also investigated. PLA/TPU</span><span style="font-family:Verdana;"> MBs were also characterized by</span> <span style="font-family:Verdana;">morphology and mechanical properties. The rheological property of the</span><span style="font-family:Verdana;"> PLA/TPU meltblown nonwoven revealed that the viscosity </span><span style="font-family:Verdana;">is increasing as the amount of TPU is increasing in the blend, PLA/TPU</span><span style="font-family:Verdana;"> melt</span></span><span style="font-family:Verdana;">blown nonwovens exhibited excellent mechanical properties;they are soft, </span><span style="font-family:;" "=""><span style="font-family:Verdana;">elas</span><span style="font-family:Verdana;">tic, and have certain tensile strength. New materials have potential applica</span><span style="font-family:Verdana;">tions in the medical and agri</span><span style="font-family:Verdana;">cultural field</span></span><span style="font-family:Verdana;">s</span><span style="font-family:Verdana;">. Joncryl ADR 4400 compatibilized blends showed higher</span><span style="font-family:Verdana;"> strength than simple PLA/TPU blends at the same PLA/TPU ratio.</span> 展开更多
关键词 Poly (lactic acid) Thermoplastic Polyurethane Meltblown TOUGHENING NONWOVEN
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Evaluation of in vitro and in vivo immunostimulatory activities of poly(lactic-co-glycolic acid) nanoparticles loaded with soluble and autoclaved Leishmania infantum antigens: A novel vaccine candidate against visceral leishmaniasis 被引量:1
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作者 Emrah Sefik Abamor Adil Allahverdiyev +4 位作者 Ozlem Ayse Tosyali Melahat Bagirova Tayfun Acar Zeynep Mustafaeva Serap Derman 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2019年第8期353-364,共12页
Objective: To prepare and characterize poly lactic-co-glycolic acid(PLGA) nanoparticles loaded with soluble leishmanial antigen or autoclaved leishmanial antigen and explore in vitro and in vivo immunogenicity of anti... Objective: To prepare and characterize poly lactic-co-glycolic acid(PLGA) nanoparticles loaded with soluble leishmanial antigen or autoclaved leishmanial antigen and explore in vitro and in vivo immunogenicity of antigen encapsulated nanoparticles. Methods: Water/oil/water double emulsion technique was employed to synthesize PLGA nanoparticles, and scanning electron microscopy, Fourier transform infrared spectroscopy and Zeta-potential measurements were used to identify the characteristics of nanoparticles. Cytotoxicity of synthetized nanoparticles on J774 macrophage were investigated by MTT assays. To determine the in vitro immunostimulatory efficacies of nanoparticles, griess reaction and ELISA was used to measure the amounts of NO and cytokines. During the in vivo analysis, Balb/c mice were immunized with vaccine formulations, and protective properties of nanoparticles were measured by Leishman Donovan unit in the liver following the infection. Cytokine levels in spleens of mice were determined by ELISA. Results: MTT assay showed that neither soluble leishmanial antigen nor autoclaved leishmanial antigen encapsulated nanoparticles showed cytotoxicity against J774 macrophage cells. Contrary to free antigens, both autoclaved leishmanial antigen-nanoparticle and soluble leishmanial antigen-nanoparticle formulations led to a 10 and 16-fold increase in NO amounts by macrophages, respectively. Leishman Donovan unit calculations revealed that soluble leishmanial antigen-nanoparticles and autoclaved leishmanial antigen-nanoparticles yielded 52% and 64% protection against visceral leishmaniasis in mouse models. Besides, in vitro and in vivo tests demonstrated that by increasing IFN-γ and IL-12 levels and inhibiting IL-4 and IL-10 secretions, autoclaved leishmanial antigen-nanoparticles and soluble leishmanial antigennanoparticles triggered Th1 immune response. Conclusions: Both autoclaved leishmanial antigen-nanoparticles and soluble leishmanial antigen-nanoparticles formulations provide exceptional in vitro and in vivo immunostimulatory activities. Hence, PLGA-based antigen delivery systems are recommended as potential vaccine candidates against visceral leishmaniasis. 展开更多
关键词 VISCERAL LEISHMANIASIS Vaccine Delivery IMMUNOSTIMULANT Poly lactic-co-glycolic acid(PLGA) Nanoparticle
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Synthesis and characterization of new biodegradable thermosensitive polyphosphazenes with lactic acid ester and methoxyethoxyethoxy side groups
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作者 Bi, Yun Mei Gong, Xiao Ying +3 位作者 Wang, Wen Zhao Yu, Li Hu, Min Qi Shao, Li Dong 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第2期237-241,共5页
Two novel biodegradable thermosensitive polyphosphazenes with lactic acid ester and methoxyethoxyethoxy side groups were synthesized via the macromolecular substitution reactions of poly(dichlorophosphazene) with the ... Two novel biodegradable thermosensitive polyphosphazenes with lactic acid ester and methoxyethoxyethoxy side groups were synthesized via the macromolecular substitution reactions of poly(dichlorophosphazene) with the sodium salt of lactic acid ester and sodium methoxyethoxyethoxide.Their structures were confirmed by ^(31)p NMR,~1H NMR,^(13)C NMR,IR,DSC,and elemental analysis.The lower critical solution temperature(LCST) behavior in water and in vitro degradation property of the polymers was investigated.The... 展开更多
关键词 POLYPHOSPHAZENE lactic acid ester Methoxyethoxyethoxy BIODEGRADATION Thermosensitive polymer
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Synthesis and Characterization of a Novel Functional Biodegradable Copolymer-Poly(lactic acid-4-hydroxyproline-polyethylene glycol)
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作者 Jiu Fang DUAN Yu Bin ZHENG 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第8期1125-1128,共4页
A series of poly(lactic acid-4-hydroxyproline-polyethylene glycol) (PLA-Hpr-PEG) copolymers were synthesized by direct melt copolymerization of D,L-lactic acid and 4-hydroxyproline with different feed amount of po... A series of poly(lactic acid-4-hydroxyproline-polyethylene glycol) (PLA-Hpr-PEG) copolymers were synthesized by direct melt copolymerization of D,L-lactic acid and 4-hydroxyproline with different feed amount of polyethylene glycol (PEG) 0.1%, 0.5%, 1% and 5%, respectively. The properties of these copolymers were characterized by using IR spectroscopy, proton nuclear magnetic resonance (1H-NMR) spectroscopy, gel permeation chromatography (GPC), X-ray diffraction and differential scaning calorimetry (DSC). PLA-Hpr-PEG are amorphous copolymers. Copolymers showed increasing water uptake capacity with increasing PEG percentage in the feed, which result in an increasing degradable rate in phosphate buffer solution (pH 7.4) at 37℃. 展开更多
关键词 lactic acid 4-hydroxyproline polyethylene glycol.
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Role of Lactic Acid Bacteria-Myeloperoxidase Synergy in Establishing and Maintaining the Normal Flora in Man
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作者 Robert C. Allen Jackson T. Stephens Jr. 《Food and Nutrition Sciences》 2013年第11期67-72,共6页
Lactic acid bacteria (LAB) are incapable of cytochrome synthesis and lack the heme electron transport mechanisms required for efficient oxygen-based metabolism. Consequently, LAB redox activity is flavoenzyme-based an... Lactic acid bacteria (LAB) are incapable of cytochrome synthesis and lack the heme electron transport mechanisms required for efficient oxygen-based metabolism. Consequently, LAB redox activity is flavoenzyme-based and metabolism is fermentative, producing lactic acid, and in many cases, hydrogen peroxide (H2O2). Despite this seeming metabolic limitation, LAB dominate in the normal flora of the mouth, vagina and lower gastrointestinal tract in man. Myeloperoxidase (MPO) is produced by the neutrophil leukocytes and monocytes that provide the innate phagocyte defense against infecting pathogens. MPO is unique in its ability to catalyze the H2O2-dependent oxidation of chloride (Cl-) to hypochlorite (OCl-). In turn, this OCl- directly reacts with a second H2O2 to produce singlet molecular oxygen (), a metastable electronic excitation state of oxygen with a microsecond lifetime that restricts its combustive reactivity within a submicron radius of its point of generation. Each day a healthy human adult produces about a hundred billion neutrophils containing about 4 femtograms MPO per neutrophil. Inflammatory states and G-CSF treatment increase both neutrophil production and the quantity of MPO per neutrophil. After a short circulating lifetime, neutrophils leave the blood and migrate into body spaces including the mouth, vagina, urinary tract, and gastrointestinal tract. Greater than a hundred thousand neutrophils are lavaged from the mouths of healthy humans;the quantity lavaged is proportional to the blood neutrophil count. MPO selectively and avidly binds to most Gram-positive and all Gram-negative bacteria tested, but LAB do not show significant MPO binding. Neutrophils migrating to normal flora sites release MPO into the LAB-conditioned milieu containing adequate acidity and H2O2 to support extra-phagocyte MPO microbicidal action. In combination, LAB plus MPO exert a potent synergistic microbicidal action against high MPO-binding microbes. This LAB-MPO synergy provides a mechanism for the establishment and maintenance of LAB in the normal flora of man. 展开更多
关键词 MYELOPEROXIDASE lactic acid Bacteria Hydrogen PEROXIDE HYPOCHLORITE SINGLET Oxygen SELECTIVE Binding SELECTIVE Microbicidal Action Normal Flora
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Isolation and Characterization of Lactic Acid Bacteria Producing Bacteriocin like Inhibitory Substance (BLIS) from “Gappal”, a Dairy Product from Burkina Faso
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作者 Abel Tankoano Michel Bakar Diop +4 位作者 Hagrétou Sawadogo-Lingani Malick Mbengue Donatien Kaboré Yves Traoré Aly Savadogo 《Advances in Microbiology》 2019年第4期343-358,共16页
Indigenous fermented foods are known for their nutritional and functional properties but they are often spoiled by pathogenic bacteria that can constitute a food safety problem. “Gappal” is a no-thermal treat food b... Indigenous fermented foods are known for their nutritional and functional properties but they are often spoiled by pathogenic bacteria that can constitute a food safety problem. “Gappal” is a no-thermal treat food based on millet dough and milk and its production conditions can constitute a food safety problem. The aim of this study was to screen and identify LAB producing Bacteriocin-like inhibitory substances using a matrix similar to “Gappal”. The detection of potential BLIS was first performed using overlaid method after enrichment of samples in whey and millet dough. The isolates demonstrating inhibiting area were preselected, purified and tested for the presence of antibacterial properties using their neutralized cell-free culture supernatant and subsequently treated with catalase in combination with protease, pepsin or trypsin. The antimicrobial effect of two isolates (Gbf48 and Gbf50) after growth on MRS broth over 12 h at 30?C were active against E. faecalis ATCC 19433, M. luteus ATCC 49732, S. aureus ATCC 2523, L. monocytogenes, B. megaterium, B. sphaericus and B. cereus with an activity of 2560 AU/mL. The 16S RNA gene sequencing identification indicated that these isolates are Pediococcus acidilactici. Gbf 48 and Gbf 50 could be used to improve preservative factors for a controlled fermentation of non thermal treatment fermented food for their potential of acidification adds to BLIS production. 展开更多
关键词 BACTERIOCIN lactic acid BACTERIA PEDIOCOCCUS acidilactici “Gappal” Burkina Faso
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A novel artificial nerve graft for repairing longdistance sciatic nerve defects:a self-assembling peptide nanofiber scaffold-containing poly (lactic-co-glycolic acid) conduit 被引量:5
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作者 Xianghai Wang Mengjie Pan +7 位作者 Jinkun Wen Yinjuan Tang Audra D.Hamilton Yuanyuan Li Changhui Qian Zhongying Liu Wutian Wu Jiasong Guo 《Neural Regeneration Research》 SCIE CAS CSCD 2014年第24期2132-2141,共10页
In this study, we developed a novel artificial nerve graft termed self-assembling peptide nanofiber scaffold (SAPNS)-containing poly(lactic-co-glycolic acid) (PLGA) conduit (SPC) and used it to bridge a 10-mm-... In this study, we developed a novel artificial nerve graft termed self-assembling peptide nanofiber scaffold (SAPNS)-containing poly(lactic-co-glycolic acid) (PLGA) conduit (SPC) and used it to bridge a 10-mm-long sciatic nerve defect in the rat. Retrograde tracing, behavioral testing and histomorphometric analyses showed that compared with the empty PLGA conduit implantation group, the SPC implantation group had a larger number of growing and extending axons, a markedly increased diameter of regenerated axons and a greater thickness of the myelin sheath in the conduit. Furthermore, there was an increase in the size of the neuromuscular junction and myofiber diameter in the target muscle. These findings suggest that the novel artificial SPC nerve graft can promote axonal regeneration and remyelination in the transected peripheral nerve and can be used for repairing peripheral nerve injury. 展开更多
关键词 nerve regeneration peripheral nerve defect artificial nerve graft poly(lactic-co-glycolic acid self-assembling peptide nanofiber scaffold REMYELINATION axon myelin neuromuscular junction NSFC grants neural regeneration
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