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Analysis of Active Components of Hexane Extractives of Morus alba Leaves 被引量:2
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作者 刘志明 王海英 张爽 《Agricultural Science & Technology》 CAS 2011年第1期23-25,共3页
[Objective]The aim was to explore the active compound of Morus alba leaves with the analysis of active components of hexane extractives of M.alba leaves.[Method]Antibacterial assays of hexane extractives of M.alba lea... [Objective]The aim was to explore the active compound of Morus alba leaves with the analysis of active components of hexane extractives of M.alba leaves.[Method]Antibacterial assays of hexane extractives of M.alba leaves were done and the volatile components of hexane extractives of M.alba leaves with the strongest antibacterial activity were analyzed by gas chromatography-mass spectrometry(GC-MS).[Result]The results of inhibitory effect of hexane extractives of M.alba leaves on Staphylococcus aureus and Escherichia coli showed that hexane extractives of M.alba leaves collected in June,July and August had antibacterial activity against S.aureus and had no antibacterial effect against E.coli.Furthermore,hexane extractives of M.alba leaves collected in June had the strongest antibacterial activity against S.aureus(inhibition diameter 10.95 mm).The hexane extractives of M.alba leaves collected in June was analyzed by GC-MS,the main volatile components were tetradecane(16.76%),dodecane(13.20%),diisobutyl phthalate(10.26%),decane(9.10%),hexadecane(8.71%),linolenyl alcohol(7.25%),octadecane(5.88%),eicosane(3.26%),dibutyl phthalate(2.59%).[Conclusion]Linolenyl alcohol was the potential antibacterial compound. 展开更多
关键词 Morus alba Hexane extractives Active components Linolenyl alcohol Gas chromatography-mass spectrometry
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Analysis of compounds in dichloromethane extractives for Sawara Falsecypress (Chamaecyparis pisifera) outer heartwood 被引量:1
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作者 NIU Jing LIU Zhi-Ming +2 位作者 WANG Xiang-Ming XU You-Ming WANG Qing-Wen 《Journal of Forestry Research》 SCIE CAS CSCD 2007年第3期208-212,共5页
The chemical components of dichloromethane extractives for Sawara Falsecypress heartwood were analyzed with GC/MS except for basic chemical composition analysis for heartwood with Chinese standard method. 14 kinds of ... The chemical components of dichloromethane extractives for Sawara Falsecypress heartwood were analyzed with GC/MS except for basic chemical composition analysis for heartwood with Chinese standard method. 14 kinds of compounds were idenfifjed according to the computer compounds library data. The major compounds in dichloromethane extractives comprised of terpene and naphthalene derivafives. The experiments of antifungal effects of the dichloromethane extractive on Aspergillus niger were also carded out. The result showed that the dichloromethane extractive from Sawara Falsecypress has no or weak antifungal capability. 展开更多
关键词 Chamaecyparis pisifera Sawara Falsecypress Outer heartwood Dichloromethane extractives GC/MS ANTIFUNGAL
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The effect of methylbenzene/ethanol ratios on chemical composition of extractives from Eucalyptus grandis 被引量:1
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作者 ZHANG Bin WU Shu-bin GUO Da-liang 《Forestry Studies in China》 CAS 2012年第3期235-239,共5页
Chemical components of methylbenzene/ethanol extractives of Eucalyptus grandis were identified by GC/MS and different methylbenzene/ethanol solutions (9/1, 4/1, 2/1, 1/1, 1/2) were used to describe their distinction... Chemical components of methylbenzene/ethanol extractives of Eucalyptus grandis were identified by GC/MS and different methylbenzene/ethanol solutions (9/1, 4/1, 2/1, 1/1, 1/2) were used to describe their distinctions. The distributions of micro particles in each extractive were studied simultaneously. The results show that there were significant differences between the various extrac- tives, although the extractives were essentially the same, i.e., alcohols, alkanes, esters and acids. With the increase of ethanol compo- sition in the solutions, the total amount of extractives increased; in solvent with higher amounts of ethanol, some acidic structures or acids, such as glutaric acid, could be seen. An investigation of micro particles indicated that the distribution of particle size of each sample did not change greatly between the solutions. A slight decrease in size was seen with the reduction in the amount of methylbenzene. 展开更多
关键词 extractives Eucalyptus grandis micro particles
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The Oxyalkylation of Hydrophilic Black Alder Bark Extractives with Propylene Carbonate with a Focus on Green Polyols Synthesis
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作者 Alexandr Arshanitsa Matiss Pals +1 位作者 Daniela Godina Oskars Bikovens 《Journal of Renewable Materials》 EI CAS 2024年第11期1927-1948,共22页
The isolated hydrophilic black alder(Alnus glutinosa)bark extractives were characterized in terms of component and functional composition and converted at 150℃-170℃ into liquid green polyols using solvent-free and l... The isolated hydrophilic black alder(Alnus glutinosa)bark extractives were characterized in terms of component and functional composition and converted at 150℃-170℃ into liquid green polyols using solvent-free and lowtoxic base-catalyzed modification with propylene carbonate(PC).FTIR spectroscopy,HP-LC,GC,GPC,and wet chemistry methods were used to characterize the starting constituents,intermediate and final products of the reaction and to monitor the different pathways of PC conversion.The reaction of extractives as well as the model compounds,including catechol,xylose,PEG 400,and benzoic acid,with PC indicated the ability of OH groups of different origins present in the extractives to condense with equivalent amounts of PC.The polyols obtained consist of a copolymer fraction with one oxypropyl unit grafted per OH functionality of extractive components on average and oligo oxypropyl diols with a small number of carbonate linkages in the chain,obtained as a result of remaining PC homopolymerization.The domination of the oxypropylation mechanism vs.transcarbonation for PC ring opening was observed for both copolymerization and homopolymerization processes,making the process of oxypropylation with PC similar to that of conventional oxypropylation.At optimal reaction conditions,including a PC/OH ratio of 3.0 and a 24-h duration at 150°C,uniform polyols with low viscosity of~900 mPa·s^(-1),a biomass content of~27%,and an OHV of~500 mg KOH·g^(-1) were obtained.Increasing the temperature of modification allows shortening the process but drastically increases the polyol viscosity.At fixed temperature values,increasing the PC/OH ratio not only decreases the biomass content but also strongly prolongs the processing.The significantly increased duration of the process using PC as an alternative oxyalkylation agent compared to that of oxyalkylation with propylene oxide is a reasonable trade-off for using a safer and more environmentally friendly technology. 展开更多
关键词 Bark extractives propylene carbonate OXYALKYLATION POLYOLS
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Lipophilic extractives of the inner and outer barks from six different Pinus species grown in Indonesia 被引量:2
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作者 Masendra Tatsuya Ashitani +1 位作者 Koetsu Takahashi Ganis Lukmandaru 《Journal of Forestry Research》 SCIE CAS CSCD 2018年第5期1329-1336,共8页
The chemical compositions of the dichloromethane extracts of inner and outer barks from six Pinus species(P.elliotii,P.oocarpa,P.caribeae,P.merkusii,P.montezumae,and P.insularis) grown in Indonesia were investigated... The chemical compositions of the dichloromethane extracts of inner and outer barks from six Pinus species(P.elliotii,P.oocarpa,P.caribeae,P.merkusii,P.montezumae,and P.insularis) grown in Indonesia were investigated by GC and GC–MS.Generally,the amounts of extractive contents were higher in the inner bark than in the outer bark except for P.merksuii.Fatty acids,monoterpenes,sesquiterpenes,resin acids,triterpenoids,and steroids were detected and quantified.Inner and outer barks differed not only in content of these compounds but also in their composition.Fatty acids and alcohols were the major classes of lipophilic compounds in the outer bark of P.caribeae, P.insularis,and P.montezumae.Steroids and triterpenoids were the dominant compounds identified in the inner bark of P.elliotii,P.insularis,and P.merkusii.Resin acids were the most abundant group in the inner bark of P.oocarpa whereas monoterpenes and sesquiterpenes were recorded in minor quantities in both bark layers of all species. 展开更多
关键词 Bark extractive LIPOPHILIC Inner bark Outer bark Pinus spp
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Extraction and Characterization of Aucoumea klaineana Pierre (Okoume) Extractives 被引量:1
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作者 Engozogho Anris Starlin Peguy Bikoro Bi Athomo Arsene +3 位作者 Vidal Marcia Denaud Louis Safou Tchiama Rodrigue Charrier Bertrand 《Journal of Renewable Materials》 SCIE 2019年第6期517-522,共6页
In order to promote convenient strategies for the utilization of wood wastes from aucoumea klaineana pierre(okoume)timber industry,various chemical analysis were carried out on samples from different origins.Total ext... In order to promote convenient strategies for the utilization of wood wastes from aucoumea klaineana pierre(okoume)timber industry,various chemical analysis were carried out on samples from different origins.Total extractives content of the bark,sapwood and heartwood of okoume were evaluated.thermogravimetric analyses were performed and the stiasny number was calculated.it was found that the bark was richer in fatty acid of high molecular weight while the sapwood was rich in fatty acid of low molecular weight.the condensed tannins content varied according to the origin and the part of the tree.these new findings should be useful for green okoume based tannin adhesives. 展开更多
关键词 Extractibles fatty acids TANNINS POLYPHENOLS stiasny number TGA
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STUDY ON CHEMICAL CONSTITUTION OF BENZENE AND ALCOHOL EXTRACTIVES OF TRACEUTRON SINENSE OLIVE
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作者 方桂珍 孙铁华 《Journal of Northeast Forestry University》 SCIE CAS CSCD 1994年第1期88-94,共7页
The wood powder of Tetracentron Sinense Olive was extracted with the benzene and alcohol (2:1 v/v). Then, the extractive is analyzed in Gc and Gc-Ms.Twenty chemical constitutions of the extractive are separated and id... The wood powder of Tetracentron Sinense Olive was extracted with the benzene and alcohol (2:1 v/v). Then, the extractive is analyzed in Gc and Gc-Ms.Twenty chemical constitutions of the extractive are separated and identified, which are as follows: calamenene; 2. 6,10-trimethyldihexyl; 3 -methoxybenzaldehyde; Methyl- 4- methox- ybenzoate; 4- methoxyphenylacetone; 3. 4- dimethoxybenzaldehyde;. 3. 4 -dimethoxyhypnone; methyl-3. 4-dimethoxybenzoate, Methyl-4-methoxyphenylacrylate,4,4-dimethoxycabonyl-diphenylethane; Methyl-3, 4,5 - erimethoxybenzoate; Methyl - 3. 4 -dimethoxyphenylacrylate; Methyl-myristate; Methyl - palmate, Methyl- zoomarate;Methyl-stearate; Methyl-oleate; Methyl-arachidate; Methyl-behenate, Dimethyl -azelate. 展开更多
关键词 Tetracentron Sinense Olive Extractive Chemical constition
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Contributions of Extractives and Lignin to the Fractal Geometry of Inter-nal Wood Surfaces
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作者 Jinzhen Cao Lu Ning Zhao GuangjieCollege of Material Science and Technology, Beijing Forestry University, Beijing 100083, P.R. China 《Forestry Studies in China》 CAS 2003年第1期39-43,共5页
Internal wood surfaces can be treated as fractals, which are between Euclidean geometry and complete randomness. The fractal dimension Dfs is very informative in investigating the roughness of the internal surfaces of... Internal wood surfaces can be treated as fractals, which are between Euclidean geometry and complete randomness. The fractal dimension Dfs is very informative in investigating the roughness of the internal surfaces of wood. In this study, the water sorption isotherms, including adsorption and desorption isotherm, of untreated, benzene-alcohol extracted and delignified (after benzene-alcohol extracted) spruce (Cuninghamia lanceolata) were measured at 30℃. On the basis of these isotherms, the Dfs values were calculated by FHH equation, which is based on multimolecular sorption. The results showed that both groups of Dfs values (respectively calculated from adsorption and desorption isotherms) of untreated, benzene-alcohol extracted and delignified wood have same order, that is, untreated > benzene-alcohol extracted - delignified. Therefore, the conclusion can be made that the benzene-alcohol extractives have significant contribution to the fractal geometry of internal wood surfaces. Lignin also has influence on the fractal geometry, but this influence is very small while compared with that of the extractives. Moreover, the Dfs values calculated from adsorption isotherms are bigger than those from desorption isotherms. 展开更多
关键词 wood sorption isotherm benzene-alcohol extractive delignin fractal dimension
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Synthesis and Characterization of N,N'-bis(Salicylidene) Ethylenediamine: Study of Extractives Properties Versus the Copper (11) in Sulphate Medium
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作者 Houria Sadou Tayeb Benabdallah Hasnia Reffas Mohamed Hadj Youcef 《Journal of Environmental Science and Engineering(B)》 2013年第7期442-447,共6页
The synthesis and characterization of N,N'-bis(salicylidene) ethylenediamine, Salen said that were carried out. The behavior of this ligand has been studied in solution in solvent homogeneous and heterogeneous syst... The synthesis and characterization of N,N'-bis(salicylidene) ethylenediamine, Salen said that were carried out. The behavior of this ligand has been studied in solution in solvent homogeneous and heterogeneous systems in sulphate medium. The use of pH-metric titration, GRAN and JOB's methods have permitted the determination of different parameters governing the behavior of Salen in solution such as the acidity constant, the stability constant, the nature of the interaction solvent-solute, the solvation number, the stoichiometry of extracted complex etc.. Then the extraction of the Salen was finally undertaken to words the copper (II) sulfate medium. The pH of complexation, extraction time, the number of protons exchanged and the number of ligands have been finally determined. 展开更多
关键词 SALEN copper (II) metal complex acid-base behaviour liquide-liquide extraction.
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Linking starch particle physicochemical properties to functionality in medicinal plants:Insights from Polygonum multiflorum and Smilax glabra 被引量:1
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作者 Nan Wang Lingling Wu +2 位作者 Yaya Su Haifeng Tang Hailong Yuan 《Chinese Chemical Letters》 2026年第1期487-491,共5页
This study investigates the properties of high-purity starches extracted from Polygonum multiflorum(PMS)and Smilax glabra(SGS).The starches were characterized by scanning electron microscopy,Fouriertransform infrared ... This study investigates the properties of high-purity starches extracted from Polygonum multiflorum(PMS)and Smilax glabra(SGS).The starches were characterized by scanning electron microscopy,Fouriertransform infrared spectroscopy,X-ray diffraction,high-performance anion-exchange chromatography,and differential scanning calorimetry.Significant differences were observed in their morphological,physicochemical,and functional properties.PMS had a smaller particle size(13.68 μm),irregular polygonal shape,A-type,lower water absorption(62.67 %),and higher oil absorption(51.17 %).In contrast,SGS exhibited larger particles(31.75 μm),a nearly spherical shape,B-type,higher crystallinity(50.66 %),and greater amylose content(21.54 %),with superior thermal stability,shear resistance,and gelatinization enthalpy.SGS also contained higher resistant starch(83.28 %) and longer average chain length(20.58 %),but showed lower solubility,swelling power,light transmittance,and freeze-thaw stability.The physicochemical properties differences in crystal pattern and particle morphology between PMS and SGS lead to distinct behaviors during in vitro digestion and fermentation.These findings highlight the potential of medicinal plant starches in functional ingredients and industrial processes. 展开更多
关键词 Starch particle Physicochemical properties Starch function Resistant starch Starch extraction
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Artificial intelligence-enabled high-precision colony extraction and isolation system
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作者 ZHAO Xu-feng JIA Zhi-qiang +5 位作者 CHEN Wei-xue HU Peng-tao SU Xin-ran LI Jun-lin GE Ming-feng DONG Wen-fei 《中国光学(中英文)》 北大核心 2026年第1期190-204,共15页
Standard bacterial suspensions play a crucial role in microbiological diagnosis.Traditional prepar-ation methods,which rely heavily on manual operations,face challenges such as poor reproducibility,low ef-ficiency,and... Standard bacterial suspensions play a crucial role in microbiological diagnosis.Traditional prepar-ation methods,which rely heavily on manual operations,face challenges such as poor reproducibility,low ef-ficiency,and biosafety concerns.In this study,we propose a high-precision automated colony extraction and separation system that combines large-field imaging and artificial intelligence(AI)to facilitate intelligent screening and localization of colonies.Firstly,a large-field imaging system was developed to capture high-resolution images of 90 mm Petri dishes,achieving a physical resolution of 13.2μm and an imaging speed of 13 frames per second.Subsequently,AI technology was employed for the automatic recognition and localiza-tion of colonies,enabling the selection of target colonies with diameters ranging from 1.9 to 2.3 mm.Next,a three-axis motion control platform was designed,accompanied by a path planning algorithm for the efficient extraction of colonies.An electronic pipette was employed for accurate colony collection.Additionally,a bacterial suspension concentration measurement module was developed,incorporating a 650 nm laser diode as the light source,achieving a measurement accuracy of 0.01 McFarland concentration(MCF).Finally,the system’s performance was validated through the preparation of an Esckerichia coli(E.coli)suspension.After 17 hours of cultivation,E.coli was extracted four times,achieving the target concentration set by the system.This work is expected to enable rapid and accurate microbial sample preparation,significantly reducing de-tection cycles and alleviating the workload of healthcare personnel. 展开更多
关键词 artificial intelligence colony extraction and isolation large-field imaging AUTOMATION
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Coordination-driven in-situ reduction and extraction of neptunium
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作者 Huaixin Hao Shuyun Zhang +7 位作者 Xue Dong Qilong Tang Yuxiao Guo Yaoyang Liu Jing Chen Jing Su Zhipeng Wang Chao Xu 《Science China Chemistry》 2026年第2期777-783,共7页
The recycling of neptunium(Np)from nuclear wastes is crucial for the sustainable development of nuclear energy,yet it is still a challenging task owing to the complexity of Np chemistry.Precise control of oxidation st... The recycling of neptunium(Np)from nuclear wastes is crucial for the sustainable development of nuclear energy,yet it is still a challenging task owing to the complexity of Np chemistry.Precise control of oxidation state is highly desirable for the effective recovery of Np.In this study,we report an innovative strategy for Np recovery through in-situ coordination and reduction of Np(Ⅴ)in a biphasic extraction system.By leveraging the synergistic effects of coordination by a P=O donating ligand(trialkyl phosphine oxide,TRPO)and reduction by hydroquinone(HQ)in the organic phase,efficient Np(Ⅴ)-to-Np(Ⅳ)conversion and high distribution ratio(D)of Np were achieved in a single extraction contact.The reduction mechanism of Np was elucidated through spectroscopic and theoretical analyses.This work enriches the redox chemistry of Np and provides a novel pathway for Np recovery in advanced nuclear fuel cycles. 展开更多
关键词 NEPTUNIUM COORDINATION REDUCTION EXTRACTION
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Comparative Analysis of the Impact of Different Ecotypes on In Vitro Anti-Inflammatory Activity of Ethanolic Extracts of Moringa oleifera Leaves
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作者 Mario D’Ambrosio Elisabetta Bigagli +4 位作者 Lorenzo Cinci Cecilia Brunetti Edgardo Giordani Francesco Ferrini Cristina Luceri 《Phyton-International Journal of Experimental Botany》 2026年第1期23-33,共11页
Moringa oleifera(MO)is traditionally used to mitigate inflammatory-mediated disorders;however,the influence of ecotypic variation on its anti-inflammatory activity remains poorly understood.In this study,we compared t... Moringa oleifera(MO)is traditionally used to mitigate inflammatory-mediated disorders;however,the influence of ecotypic variation on its anti-inflammatory activity remains poorly understood.In this study,we compared the phytochemical composition and anti-inflammatory activity of ethanolic extracts obtained from fresh and dried leaves of four MO ecotypes(India,Paraguay,Mozambique,and Pakistan),all grown under the same outdoor conditions,as well as two commercial powders(Just Moringa and WISSA),using LPS-stimulated RAW 264.7 macrophages.Extracts from fresh leaves were 19-43%more cytotoxic than those from dried leaves,depending on the ecotype,likely due to higher cyanogenic glycoside content.Extracts from the India and Paraguay ecotypes,characterized by high levels of quercetin derivatives and caffeic acids,as well as Just Moringa,enriched in kaempferol derivatives,significantly inhibited LPS-induced nitric oxide(NO)production(p<0.05).Just Moringa and Paraguay extracts also reduced iNOS gene expression(p<0.05 and p<0.01,respectively),whereas only the Paraguay extract decreased iNOS protein levels(p<0.05).In contrast,quercetin-3-O-glucoside and rutin showed significant effects only at concentrations approximately 100-fold higher than those present in the extracts,indicating that the phytocomplex displays greater bioactivity than individual compounds.Overall,these results demonstrate that ecotypic variation strongly affects the polyphenolic composition and anti-inflammatory properties of MO leaves,highlighting the importance of reporting both origin and phytochemical composition in MO-based products. 展开更多
关键词 Moringa oleifera ECOTYPE INFLAMMATION plant extract POLYPHENOLS
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Engineering a Bilayered Scaffold as a Potential Cardiac Patch:From Scaffold Design to In Vitro Assessment
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作者 Adile Yuruk Ayhan Duzler +1 位作者 Sevil Dincer Isoglu Ismail Alper Isoglu 《Journal of Bionic Engineering》 2026年第1期394-415,共22页
In this study,we developed a novel bilayered scaffold consisting of a bottom layer composed of the Decellularized Bovine Pericardium(DP)coated with Polyaniline Nanoparticles(PANINPs)and a top layer made of an electros... In this study,we developed a novel bilayered scaffold consisting of a bottom layer composed of the Decellularized Bovine Pericardium(DP)coated with Polyaniline Nanoparticles(PANINPs)and a top layer made of an electrospun Poly(lactic-co-glycolic acid)/Gelatin(PLGA/Gel)membrane incorporated with Vascular Endothelial Growth Fac-tor(VEGF)and hawthorn extract.Functionally,the DP supplies native Extracellular Matrix(ECM)components and mechanical support,while PANINPs provide conductivity.The electrospun PLGA/Gel layer mimics fibrous ECM.It incorporates bioactives,with VEGF promoting pro-angiogenic stimulation and hawthorn extract enhanc-ing anticoagulant activity,as well as increasing surface hydrophilicity.The tissue adhesive ensures the interfacial integrity between the two layers.Decellularization efficiency was confirmed histologically using 4',6-diamidino-2-phenylindole(DAPI)and Hematoxylin-Eosin(H&E)staining.The DP exhibited a DNA content of 115.9±47.8 ng/mg DNA,compared to 982.88±395.42 ng/mg in Native Pericardium(NP).The PANINPs had an average par-ticle size of 104.94±13.7 nm.The conductivity of PANINPs-coated decellularized pericardium was measured to be 9.093±8.6×10-4 S/cm using the four-point probe method.PLGA/Gel membranes containing hawthorn extract(1%,5%,10%,and 15%w/v)and VEGF(0.1μg/mL,0.5μg/mL,and 1μg/mL)were fabricated by electrospinning,result-ing in fiber diameters between 850 and 1200 nm and pore sizes between 14 and 20μm.The anticoagulant efficiency of the membranes containing hawthorn extract reached 430 s in the Activated Partial Thromboplastin Time Assay(aPTT).Mechanical testing revealed a tensile strength of 22.70±6.33 MPa,an elongation of 53.58±10.63%,and Young's modulus of 0.67±0.10 MPa.The scaffold also exhibited over 91%cell viability and excellent cardiomyo-cyte adhesion.The hemolysis ratio was determined to be 0.421±0.191%,which confirms its blood compatibility.Our results indicate that the proposed bilayered scaffold can be a promising candidate for cardiac patch applications. 展开更多
关键词 Cardiac patch Bilayered scaffold DECELLULARIZATION ELECTROSPINNING Hawthorn extract VEGF
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Flexible High-Aspect-Ratio COF Nanofibers:Defect-Engineered Synthesis,Superelastic Aerogels,and Uranium Extraction Applications
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作者 Binbin Fan Jianyong Yu +2 位作者 Xueli Wang Yang Si Peixin Tang 《Nano-Micro Letters》 2026年第5期15-30,共16页
The lack of macro-continuity and mechanical strength of covalent organic frameworks(COFs)has significantly limited their practical applications.Here,we propose an“alcohol-triggered defect cleavage”strategy to precis... The lack of macro-continuity and mechanical strength of covalent organic frameworks(COFs)has significantly limited their practical applications.Here,we propose an“alcohol-triggered defect cleavage”strategy to precisely regulate the growth and stacking of COF grains through a moderate reversed Schiff base reaction,realizing the direct synthesis of COF nanofibers(CNFs)with high aspect ratio(L/D=103.05)and long length(>20μm).An individual CNF exhibits a biomimetic scale-like architecture,achieving superior flexibility and fatigue resistance under dynamic bending via a multiscale stress dissipation mechanism.Taking advantages of these structural features,we engineer CNF aerogels(CNF-As)with programmable porous structures(e.g.,honeycomb,lamellar,isotropic)via directional ice-template methodology.CNF-As demonstrate 100%COF content,high specific surface area(396.15 m^(2)g^(-1))and superelasticity(~0%elastic deformation after 500 compression cycles at 50%strain),outperforming most COF-based counterparts.Compared with the conventional COF aerogels,the unique structural features of CNF-A enable it to perform outstandingly in uranium extraction,with an 11.72-fold increment in adsorption capacity(920.12 mg g^(-1))and adsorption rate(89.9%),and a 2.48-fold improvement in selectivity(U/V=2.31).This study provides a direct strategy for the development of next-generation COF materials with outstanding functionality and structural robustness. 展开更多
关键词 Defect cleavage COF nanofibers Flexibility AEROGELS Uranium extraction
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Biostimulatory Influence of Commercial Seaweed Extract on Seed Emergence,Seedling Growth,and Vigor of Winter Rice
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作者 Zakia Akter Sumona Akter Jannat +5 位作者 Sheikh Md.Shibly Afroza Sultana Amdadul Hoque Amran Joairia Hossain Faria Sabina Yeasmin Md.Parvez Anwar 《Phyton-International Journal of Experimental Botany》 2026年第1期327-344,共18页
Seaweed extract contains plant growth regulators and bio-stimulants that enhance plant growth and development.In Bangladesh,winter rice(Boro rice)in the nursery bed often shows poor seed emergence and weak seedling gr... Seaweed extract contains plant growth regulators and bio-stimulants that enhance plant growth and development.In Bangladesh,winter rice(Boro rice)in the nursery bed often shows poor seed emergence and weak seedling growth due to low temperature.This problem can be addressed by using seaweed extract as a seed priming agent and bio-stimulant.The objective of this study was to evaluate the effectiveness of seaweed extract(Crop Plus)on seed emergence,seedling growth,and vigor of winter rice in the nursery.Two experiments were conducted at Bangladesh Agricultural University using BRRI dhan89.The laboratory experiment consisted of 17 treatments combining three concentrations of Crop Plus(5000,10,000 and 15,000 ppm)and four priming durations(6,12,18,and 24 h),along with hydro-priming and a no priming as control.Seed priming with 15,000 ppm for 24 h produced the highest germination percentage and superior seedling growth traits.The nursery bed experiment comprised 11 treatments combining two doses(1 mL m^(−2)and 2 mL m^(−2))of Crop Plus and five different foliar application schedules,along with a control.All treatments outperformed the control,with the best results from Crop Plus@2 mL m^(−2)applied at 20 and 30 days after sowing(DAS).Overall,the treatment involving seed priming with 15,000 ppm seaweed extract for 24 h,followed by nursery application at 2 mL m^(−2)at 20 and 30 DAS,resulted in higher germination and improved early growth of winter rice.However,further validation across multiple locations,seasons,and rice cultivars is recommended. 展开更多
关键词 Seaweed extract seed invigoration foliar feeding GERMINATION seedling vigor PADDY
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Straightforward and versatile construction of phenanthroline-derived diamide ligands for f-block element extraction
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作者 Dong Fang Xiaofan Yang +1 位作者 Fengxin Gao Chengliang Xiao 《Chinese Chemical Letters》 2026年第1期602-605,共4页
As an important class of phenanthroline derivatives containing soft N and hard O donor atoms,the laborious syntheses of unsymmetrical 1,10-phenanthroline-derived diamide ligands(DAPhen) have hindered its extensive stu... As an important class of phenanthroline derivatives containing soft N and hard O donor atoms,the laborious syntheses of unsymmetrical 1,10-phenanthroline-derived diamide ligands(DAPhen) have hindered its extensive study.In this work,we first report a convenient synthetic method for the construction of DAPhen using Friedländer reaction by two facile steps(vs.previous 12 steps).A variety of DAPhen ligands are readily available,especially unsymmetrical ones,which give us a platform to systematically study the substituent effect on f-block elements extraction performance.The performance of unsymmetrical extractants is experimentally confirmed to falls between that of their corresponding symmetrical extractants by extracting UO_(2)^(2+) as the representative f-block element.This work provides a direct and versatile method to synthesize symmetrical and unsymmetrical DAPhen,which paves way for the investigations on their coordination properties with metal ions and other applications. 展开更多
关键词 Phenanthroline diamide ligand Friedlander reaction UNSYMMETRICAL SYMMETRICAL Solvent extraction
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Cutting-edge aminated conjugated microporous poly(aniline)s enabled high-performance membrane for seawater uranium extraction
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作者 Xiaoxia Ye Bingqing Huang +7 位作者 Xueying Chen Yaping Wang Zhihong Zheng Yifan Liu Yuancai Lv Chunxiang Lin Jian Huang Jie Chen 《Green Energy & Environment》 2026年第1期181-194,共14页
The extraction of uranium from seawater via membrane adsorption is a promising strategy for ensuring a long-term supply of uranium and the sustainability of nuclear energy.However,this approach has been hindered by th... The extraction of uranium from seawater via membrane adsorption is a promising strategy for ensuring a long-term supply of uranium and the sustainability of nuclear energy.However,this approach has been hindered by the longstanding challenge of identifying sustainable membrane materials.In response,we propose a prototypal hybridization strategy to design a novel series of aminated conjugated microporous polymer(CMPN)@collagen fiber membrane(COLM).These sustainable and low-cost membrane materials allow a rapid and high-affinity kinetic to capture 90%of the uranium in just 30 min from 50 ppm with a high selectivity of Kd>105 mL·g^(−1).They also afford a robustly reusable adsorption capacity as high as 345 mg·g^(−1)that could harvest 1.61 mg·g^(−1)of uranium in a short 7-day real marine engineering in Fujian Province,even though suffered from very low uranium concentration of 3.29μg·L^(−1)and tough influence of salts such as 10.77 g·L^(−1)of Na^(+),1.75μg·L^(−1)of VO_(3)^(−)etc.in the rough seas.The structural evidence from both experimental and theoretical studies confirmed the formation of favorable chelating motifs from the amino group on CMPN-COLM,and the intensification by the synergistic effect from the size-sieving action of CMPN and the capillary inflow effect of COLM. 展开更多
关键词 Conjugated microporous polymer Collagen fiber MEMBRANE Seawater Uranium extraction
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Enhanced Multi-Scale Feature Extraction Lightweight Network for Remote Sensing Object Detection
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作者 Xiang Luo Yuxuan Peng +2 位作者 Renghong Xie Peng Li Yuwen Qian 《Computers, Materials & Continua》 2026年第3期2097-2118,共22页
Deep learning has made significant progress in the field of oriented object detection for remote sensing images.However,existing methods still face challenges when dealing with difficult tasks such as multi-scale targ... Deep learning has made significant progress in the field of oriented object detection for remote sensing images.However,existing methods still face challenges when dealing with difficult tasks such as multi-scale targets,complex backgrounds,and small objects in remote sensing.Maintaining model lightweight to address resource constraints in remote sensing scenarios while improving task completion for remote sensing tasks remains a research hotspot.Therefore,we propose an enhanced multi-scale feature extraction lightweight network EM-YOLO based on the YOLOv8s architecture,specifically optimized for the characteristics of large target scale variations,diverse orientations,and numerous small objects in remote sensing images.Our innovations lie in two main aspects:First,a dynamic snake convolution(DSC)is introduced into the backbone network to enhance the model’s feature extraction capability for oriented targets.Second,an innovative focusing-diffusion module is designed in the feature fusion neck to effectively integrate multi-scale feature information.Finally,we introduce Layer-Adaptive Sparsity for magnitude-based Pruning(LASP)method to perform lightweight network pruning to better complete tasks in resource-constrained scenarios.Experimental results on the lightweight platform Orin demonstrate that the proposed method significantly outperforms the original YOLOv8s model in oriented remote sensing object detection tasks,and achieves comparable or superior performance to state-of-the-art methods on three authoritative remote sensing datasets(DOTA v1.0,DOTA v1.5,and HRSC2016). 展开更多
关键词 Deep learning object detection feature extraction feature fusion remote sensing
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Occurrence modes and comprehensive utilization of critical metal resources associated with coal:A review
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作者 Qin Zhang Wei Cheng +6 位作者 Tiebin Zhang Hongbo Liu Jiwei Yuan Aoao Chen Tingshun Wang Qian Liu Jianghe Wang 《International Journal of Mining Science and Technology》 2026年第2期277-293,共17页
Coal serves not only as a crucial energy resource but also as a significant reservoir of critical metal elements,including Lithium(Li),Gallium(Ga),Germanium(Ge),and rare earth elements(REE).This paper provides a syste... Coal serves not only as a crucial energy resource but also as a significant reservoir of critical metal elements,including Lithium(Li),Gallium(Ga),Germanium(Ge),and rare earth elements(REE).This paper provides a systematic review of the enrichment characteristics,occurrence modes,and comprehensive utilization potential of these critical metals in coal.Globally,the distribution of these metal resources exhibits significant regional heterogeneity.While the concentration in most coals falls below industrial cut-off grades,anomalous enrichment in specific coal basins results in Li,Ga,Ge,and REE concentrations far exceeding global averages,highlighting their considerable potential as unconventional metal deposits.The occurrence modes of these metals are diverse:Li is primarily hosted in mineral phases;Ga exists in inorganic,organic,and complex forms;Ge shows a strong association with organic matter;and REE are mainly present in adsorbed/isomorphic forms within clay minerals,while also displaying organic affinity.Direct extraction of metals from raw coal is often cost-prohibitive;effective recovery is therefore more feasible when integrated with coal processing.Metals are further enriched in solid wastes such as coal gangue,fly ash,and bottom ash,from which recovery is more economically and technically viable.Current comprehensive utilization primarily employs integrated mineral processing-hydrometallurgy approaches.Future research should focus on elucidating the precise occurrence forms of metals in coal and solid wastes,optimizing pre-treatment methods,and selecting effective activators and leachants.Advancing the synergistic extraction and green recovery of multiple associated resources from coal and its by-products is essential for achieving high-value,comprehensive utilization of coal-based resources. 展开更多
关键词 Coal-associated resources Lithium GALLIUM GERMANIUM Rare carth elements Extraction and separation
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