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“聚土地”与新型农业经营体系实现形式分析 被引量:2
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作者 薛国琴 杨俊超 《农业经济》 北大核心 2015年第10期52-54,共3页
"型农业经营体系具有集约化、专业化、组织化、社会化等特征,如何构建、运行新型农业经营体系?文章以安徽省绩溪县的"聚土地"项目为分析对象,通过对其运作模式的分析,发现"聚土地"具有家庭经营、规模经营、多... "型农业经营体系具有集约化、专业化、组织化、社会化等特征,如何构建、运行新型农业经营体系?文章以安徽省绩溪县的"聚土地"项目为分析对象,通过对其运作模式的分析,发现"聚土地"具有家庭经营、规模经营、多元化主体、商品化生产等特征,是新型农业经营体系的较好实现形式。文章认为,通过推进农村土地制度改革、建立多层次农业社会化服务体系、培育多元农业经营主体,有助于构建新型农业经营体系。 展开更多
关键词 “聚土地” 新型农业经营体系 新型农业经营主体
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Effects of Soybean Oligosaccharides Extracted from Defatted Soybean Meal on Gut Microbiota and Metabolites during in Vitro Fermentation Process 被引量:1
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作者 SU Tingting YANG Xiyuan +6 位作者 YU Qiaoru WU Mengna XU Lei WANG Hui MU Xindi YAO Di WANG Changyuan 《食品科学》 北大核心 2025年第11期164-179,共16页
To investigate the in vitro digestion and fermentation properties of soybean oligosaccharides(SBOS)extracted from defatted soybean meal,the changes in monosaccharide composition and molecular mass were analyzed.Subseq... To investigate the in vitro digestion and fermentation properties of soybean oligosaccharides(SBOS)extracted from defatted soybean meal,the changes in monosaccharide composition and molecular mass were analyzed.Subsequently,the effect of SBOS on microbial community structure and metabolites was studied by 16S rRNA gene sequencing and untargeted metabolomics based on liquid chromatography-mass spectrometry.Results showed that SBOS was not easily enzymolyzed during simulated digestion and could reach the large intestine through the digestive system.The significant decrease in the molecular mass of SBOS after in vitro fermentation indicated its utilization by the gut microbiota,which increased the contents of short-chain fatty acids and lactic acid,thereby reducing the pH of the fermentation broth.Moreover,the core community was found to consist of Blautia,Lactobacillaceae,and Pediococcus.SBOS up-regulated beneficial differential metabolites such as myo-inositol,lactose,and glucose,which were closely related to galactose,amino sugar,and nucleotide sugar metabolism.This study will provide a reference for exploring the relationship between the gut microbiota and the metabolites of SBOS,and provide a basis for the development and application of SBOS as an ingredient for functional products. 展开更多
关键词 soybean oligosaccharides simulated digestion fecal fermentation gut microbiota METABOLITES
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Establishment of a field visualization detection method for multiplex recombinase polymerase amplification combined with CRISPR/Cas12a in genetically modified crops 被引量:1
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作者 YAN Jingying NI Liang +2 位作者 SHEN Xingyu LÜ Bingtao LI Yu 《浙江大学学报(农业与生命科学版)》 北大核心 2025年第3期391-401,共11页
With the approval of more and more genetically modified(GM)crops in our country,GM safety management has become more important.Transgenic detection is a major approach for transgenic safety management.Nevertheless,a c... With the approval of more and more genetically modified(GM)crops in our country,GM safety management has become more important.Transgenic detection is a major approach for transgenic safety management.Nevertheless,a convenient and visual technique with low equipment requirements and high sensitivity for the field detection of GM plants is still lacking.On the basis of the existing recombinase polymerase amplification(RPA)technique,we developed a multiplex RPA(multi-RPA)method that can simultaneously detect three transgenic elements,including the cauliflower mosaic virus 35S gene(CaMV35S)promoter,neomycin phosphotransferaseⅡgene(NptⅡ)and hygromycin B phosphotransferase gene(Hyg),thus improving the detection rate.Moreover,we coupled this multi-RPA technique with the CRISPR/Cas12a reporter system,which enabled the detection results to be clearly observed by naked eyes under ultraviolet(UV)light(254 nm;which could be achieved by a portable UV flashlight),therefore establishing a multi-RPA visual detection technique.Compared with the traditional test strip detection method,this multi-RPA-CRISPR/Cas12a technique has the higher specificity,higher sensitivity,wider application range and lower cost.Compared with other polymerase chain reaction(PCR)techniques,it also has the advantages of low equipment requirements and visualization,making it a potentially feasible method for the field detection of GM plants. 展开更多
关键词 genetically modified crop recombinase polymerase amplification CRISPR/Cas12a field detection
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Characteristics and differential diagnosis of common verrucous proliferative skin diseases under dermoscopy and reflectance confocal microscopy 被引量:1
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作者 ZHOU Lu FU Yule +7 位作者 HUANG Jian TANG Zhen LU Jianyun TAN Lina WANG Dan ZENG Jinrong WANG Jia GAO Lihua 《中南大学学报(医学版)》 北大核心 2025年第3期358-365,共8页
Objective:Verrucous epidermal nevus(VEN),seborrheic keratosis(SK),verruca plana(VP),verruca vulgaris(VV),and nevus sebaceous(NS)are common verrucous proliferative skin diseases with similar clinical appearances,often ... Objective:Verrucous epidermal nevus(VEN),seborrheic keratosis(SK),verruca plana(VP),verruca vulgaris(VV),and nevus sebaceous(NS)are common verrucous proliferative skin diseases with similar clinical appearances,often posing diagnostic challenges.Dermoscopy and reflectance confocal microscopy(RCM)can aid in their differentiation,yet their specific features under these tools have not been systematically described.This study aims to summarize and analyze the dermoscopic and RCM features of VEN,SK,VP,VV,and NS.Methods:A total of 121 patients with histopathologically confirmed verrucous proliferative skin diseases were enrolled.Dermoscopy and RCM imaging was used to observe and analyze the microscopic features of these conditions.Results:Under dermoscopy,the 5 diseases displayed distinct characteristics:VEN typically showed gyriform structures;SK was characterized by gyriform structures,comedo-like openings,and milia-like cysts;VP and VV featured dotted vessels and frogspawn-like structures;NS presented as brownish-yellow globules.RCM revealed shared features such as hyperkeratosis and acanthosis across all 5 diseases.Specific features included gyriform structures and elongated rete ridges in VEN;pseudocysts and gyriform structures in SK;evenly distributed ring-like structures in VP;vacuolated cells and papillomatous proliferation in VV;and frogspawn-like structures in NS.Conclusion:These 5 verrucous proliferative skin conditions exhibit distinguishable features under both dermoscopy and RCM.The combination of these 2 noninvasive imaging modalities holds significant clinical value for the differential diagnosis of verrucous proliferative skin diseases. 展开更多
关键词 reflectance confocal microscopy DERMOSCOPY verrucous proliferation verrucous epidermal nevus seborrheic keratosis verruca plana verruca vulgaris nevus sebaceous
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Biosynthesis of xylo-oligosaccharides from wheat straw xylan through the synergistic hydrolysis by xylanase Xyn11A and arabinofuranosidase Abf62A
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作者 HU Die XU Daozhu +3 位作者 LU Zhiyi TANG Wei FAN Bo HE Yucai 《合成生物学》 北大核心 2025年第4期972-986,共15页
Xylo-oligosaccharides(XOSs)are a category of functional oligosaccharides primarily composed of 2-7 xylose units linked byβ-1,4 glycosidic bonds.They are recognized as soluble dietary fibers with prebiotic properties.... Xylo-oligosaccharides(XOSs)are a category of functional oligosaccharides primarily composed of 2-7 xylose units linked byβ-1,4 glycosidic bonds.They are recognized as soluble dietary fibers with prebiotic properties.Recently, there has been significant interest in manufacturing XOSs from xylan extracted from lignocellulosic biomass using enzyme catalysis under mild conditions. In this work, the arabinofuranosidase Abf62A gene was cloned from Aspergillus usamii genomic DNA through sequential molecular processes and expressed in Pichia pastoris X33. The xylan (100 g/L) extracted xylan in wheat straw (WS) was biologically hydrolyzed into 50.32 g/L of XOSs by xylanase Xyn11A (300 U/g substrate) and arabinofuranase Abf62A (20 U/g substrate), which indicated a notable synergistic effect compared to the 34.42 g/L XOSs produced via Xyn11A. The 50.32 g/L of XOSs products comprised xylobiose (31.71 g/L), xylotriose (15.92 g/L), xylotetraose (1.65 g/L) and xylopentaose (1.04 g/L). Notably, the combined content of xylobiose and xylotriose accounted for up to 94.7%. The XOSs purified from the enzyme hydrolysate could effectually scavenge free radicals, and the antioxidant activity was more than 90%. In summary, XOSs were biologically manufactured from wheat straw xylan through the synergistic biocatalysis via xylanase and arabinofuranosidase Abf62A in a green and sustainable way, rending one kind of prebiotic oligosaccharides with substantial positive effects on human and animal health. 展开更多
关键词 ARABINOFURANOSIDASE XYLANASE xylo-oligosaccharides XYLAN BIOSYNTHESIS
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Comparison of Properties Between Polypropylene and Polycaprolactam Materials in Common Automobile Environments
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作者 DIAO Shuai DONG Jinghan +2 位作者 ZHAO Yiquan YANG Wenxuan ZHANG Zhisong 《材料导报》 北大核心 2025年第S1期724-728,共5页
To compare the suitable working conditions of polypropylene(PP)and polycaprolactam(PA6)materials in actual use in automobiles,the effects of different temperature aging and different reagents on the mechanical propert... To compare the suitable working conditions of polypropylene(PP)and polycaprolactam(PA6)materials in actual use in automobiles,the effects of different temperature aging and different reagents on the mechanical properties of the two materials,such as tensile,bending,compression,and impact were studied.The results indicate that the short⁃term low⁃temperature environment had no much effect on the mechanical properties of PP and PA6.After long⁃term thermal aging at 80℃,the strength of PP and PA6 increased while their toughness decreased.After short⁃term thermal aging at 120℃,PP strength decreases and toughness increases,while PA6 strength increases and toughness decreases.The soaking of glass water and car shampoo had no much effect on the mechanical properties of PP,but had a significant impact on the mechanical properties of PA6.With the increase of soaking time,the strength of PA6 significantly decreases and the toughness significantly increases.The soaking of 95#gasoline had no much effect on the mechanical properties of PA6,but has a significant impact on the mechanical properties of PP.After 720 h of soaking,the retention rates of the tensile strength,bending strength,and compressive strength of PP were all less than 80%,while the retention rate of the impact strength of the cantilever beam was 160.4%. 展开更多
关键词 POLYPROPYLENE POLYCAPROLACTAM AUTOMOBILE environmental aging material property
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Boron-containing copolymers as environmentally friendly lubricant additives
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作者 Hua Xue Fengchun Liang +4 位作者 Weili Yang Qun He Meirong Cai Feng Zhou Weifeng Bu 《日用化学工业(中英文)》 北大核心 2025年第1期1-11,共11页
Increasing environmental concerns about limiting harmful emissions has necessitated sulfur-and phosphorus-free green lubricant additives.Although boron-containing compounds have been widely investigated as green lubri... Increasing environmental concerns about limiting harmful emissions has necessitated sulfur-and phosphorus-free green lubricant additives.Although boron-containing compounds have been widely investigated as green lubricant additives,their macromolecular analogs have been rarely considered yet to develop environmentally friendly lubricant additives.In this work,a series of boron-containing copolymers have been synthesized by free-radical copolymerization of stearyl methacrylate and isopropenyl boronic acid pinacol ester with different feeding ratios(S_(n)-r-B_(m),n=1,m=1/3,1,2,3,5,9).The resulting copolymers of S_(n)-r-B_(m)(n=1,m=1/3,1,2,3,5)are readily dispersed in the PAO-10 base oil and form micelle-like aggregates with hydrodynamic diameters ranging from 9.7 to 52 nm.SRV-IV oscillating reciprocating tribological tests on ball-on-flat steel pairs show that compared with the base oil of PAO-10,the friction coefficients and wear volumes of the base oil solutions of S_(n)-r-B_(m)decrease considerably up to 62%and 97%,respectively.Moreover,the base oil solution of S_(1)-r-B_(1)exhibits an excellent load-bearing capacity of(850±100)N.These superior lubricating properties are due to the formation of protective tribofilms comprising S_(n)-r-B_(m),boron oxide,and iron oxide compounds on the lubricated steel surface.Therefore,the boron-containing copolymers can be regarded as a novel class of environmentally friendly lubricating oil macroadditives for efficient friction and wear reduction without sulfur and phosphorus elements. 展开更多
关键词 friction and wear reduction lubricant additives boron-containing copolymers POLYMERIZATION
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A rapid soil DNA extraction method applied to field detection
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作者 YAN Jingying NI Liang +1 位作者 LI Kunfeng SHEN Xingyu 《浙江大学学报(农业与生命科学版)》 北大核心 2025年第4期586-595,共10页
Soil DNA extraction,such as microbial community analysis and gene drift detection,is an important basis for multiple analyses in different fields.Nevertheless,the soil DNA extraction methods for field detection are st... Soil DNA extraction,such as microbial community analysis and gene drift detection,is an important basis for multiple analyses in different fields.Nevertheless,the soil DNA extraction methods for field detection are still lacking.This study established a rapid soil DNA extraction(RSDE)method that can be used in field detection.In this method,we first utilized the optimized lysate to isolate DNA from soil and then used a filtration membrane and a DNA adsorption membrane to purify the DNA via the column method.Moreover,we used the pressure from the syringe instead of the conventional centrifugal force of the centrifuge to assist the sample filtration,resulting in very low requirements for this method,with an extraction time of less than 20 min.Furthermore,we demonstrated that the RSDE method was applicable for DNA extraction from different types of soils,with the demand for soil samples as low as 0.1 g and that the amount of obtained DNA was,to some extent,greater than that obtained by a commercial kit.Further analysis revealed that this extracted genomic DNA can be used directly for polymerase chain reaction(PCR)analysis,including ordinary PCR,real-time fluorescent quantitative PCR,and recombinase polymerase amplification(RPA)-CRISPR/Cas12a visual assays.In addition,we demonstrated that this method can be used to extract DNA from residual plant roots in addition to soil microbes,which lays a foundation for the comprehensive analysis of soil plants and microorganisms.In summary,the RSDE method proposed in this study may have wide application prospects. 展开更多
关键词 soil DNA DNA extraction field detection polymerase chain reaction recombinase polymerase amplification(RPA)-CRISPR/Cas12a
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The chitosan encapsulation strategy inhibits the dissolution of MoS_(2)/ZnO nanoparticles in water disinfection
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作者 Yutao Xie Yunpeng Yu Feng Gao 《中国科学技术大学学报》 北大核心 2025年第3期28-38,27,I0002,共13页
The combination of solar disinfection and photocatalysis technology presents a viable solution for eliminating harmful pathogenic microorganisms from water.However,some photocatalysts(e.g.,zinc oxide-based composites)... The combination of solar disinfection and photocatalysis technology presents a viable solution for eliminating harmful pathogenic microorganisms from water.However,some photocatalysts(e.g.,zinc oxide-based composites)are susceptible to pH-dependent dissolution in water,which can result in the loss of photocatalysts and additional environ-mental pollution.To obtain zinc oxide-based composites with low dissolution and high antibacterial efficiency for pho-tocatalytic water disinfection,we prepared MoS_(2)/ZnO@CS composites via a precipitation method to encapsulate chitosan(CS)around MoS_(2)/ZnO.The amino groups in the CS molecules act as storerooms for hydrogen ions,which inhibits the dissolution of zinc oxide.In addition,the MoS_(2)/ZnO@CS composites exhibit high production of reactive oxygen species(ROS)and broad-spectrum antibacterial activity under simulated solar irradiation(0.1 W·cm^(-2)).This makes it an excellent antibacterial agent for solar disinfection in water treatment. 展开更多
关键词 ZnO MoS_(2) CHITOSAN ANTIBACTERIAL water disinfection
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为中国“强起来”聚合磅礴力量
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作者 叶小文 《北京社会科学》 CSSCI 北大核心 2017年第12期7-11,共5页
中华民族要实现伟大飞跃,就要聚合磅礴的力量。而中国共产党是一个特别善于"聚""合"的政党。中华民族要持续伟大飞跃,就要增添特殊的"核动力"。这种能够持续发展、取之不竭用之不尽的"核动力"... 中华民族要实现伟大飞跃,就要聚合磅礴的力量。而中国共产党是一个特别善于"聚""合"的政党。中华民族要持续伟大飞跃,就要增添特殊的"核动力"。这种能够持续发展、取之不竭用之不尽的"核动力",来自坚定不移的改革开放政策和中华传统文化中的优秀基因。中国共产党由此探索出了一条与世界各国共商、共建、共享,遵循平等、追求互利的新路——"一带一路"。 展开更多
关键词 十九大 “聚”“合” “核动力” 文化自信 “一带一路”
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Syntheses,characterization,and luminescence properties of Yb(Ⅲ)-based one-dimensional chain coordination polymer
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作者 CHEN Wanting MIAO Chufei +4 位作者 LIU Yan ZHENG Bobi ZHENG Xiaoyu XU Han TIAN Jumei 《无机化学学报》 北大核心 2025年第8期1672-1680,共9页
One Yb(Ⅲ)-based coordination polymer,{[Yb(H_(2)dhtp)1.5(H_(2)O)_(4)]·3H_(2)O}n(1)(H_(4)dhtp=2,5-dihydroxytere-phthalic acid),was fabricated and structurally characterized by single-crystal X-ray diffraction,IR,p... One Yb(Ⅲ)-based coordination polymer,{[Yb(H_(2)dhtp)1.5(H_(2)O)_(4)]·3H_(2)O}n(1)(H_(4)dhtp=2,5-dihydroxytere-phthalic acid),was fabricated and structurally characterized by single-crystal X-ray diffraction,IR,powder X-ray diffraction,X-ray diffraction,and elemental analysis.Complex 1 displays a 1D chain structure,and belongs to P1 group.The solid-state luminescent spectrum of 1 showed an emission band with the maximum at 508 nm(λex=408 nm).It exhibited the emission characteristic of the H_(4)dhtp ligand.The fluorescence of 1 in water displayed the stron-gest intensity.In detecting various metal ions,adding Zr^(4+)led to a blue shift in fluorescence,accompanied by an increase in intensity,whereas the presence of Fe^(3+)resulted in a decrease in luminescence.The changes observed in the IR spectrum indicate an interaction between Fe^(3+)/Zr^(4+)and complex 1,resulting in the variation of luminescence properties. 展开更多
关键词 coordination polymers STRUCTURE LUMINESCENCE
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Methanolysis/Hydrolysis of Polyethylene Terephthalate Over Cu-Mg-Al Oxides Catalysts Promoted by Trace Water
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作者 NIU Tiantian LIANG Changhai CHEN Xiao 《石油学报(石油加工)》 北大核心 2025年第3期707-719,共13页
With the aim to effectively depolymerize polyethylene terephthalate(PET)under mild reaction conditions,PET methanolysis and dimethyl terephthalate(DMT)hydrolysis are integrated in a catalyst system.Firstly,methanolysi... With the aim to effectively depolymerize polyethylene terephthalate(PET)under mild reaction conditions,PET methanolysis and dimethyl terephthalate(DMT)hydrolysis are integrated in a catalyst system.Firstly,methanolysis of PET to DMT is achieved over Cu-Mg-Al oxide catalyst.Next,terephthalic acid(TPA)is prepared by DMT hydrolysis.It is found that hydrolysis of DMT to TPA can be promoted by introducing trace amount of water in this catalyst system.CuO-MgO-4.5Al_2O_(3)catalyst demonstrates the excellent catalytic performance for the depolymerization of PET with high conversion rate and TPA yield(100%and 99.5%,respectively)after reaction at 160℃for 6 h,which provides a new idea for the depolymerization of PET. 展开更多
关键词 polyethylene terephthalate terephthalic acid METHANOLYSIS HYDROLYSIS Cu-Mg-Al oxide
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论江西旅游业的“聚湖实心”战略——以建设鄱阳湖生态经济区为视角
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作者 杨丽琼 《求实》 CSSCI 北大核心 2010年第10期60-62,共3页
随着鄱阳湖生态经济区建设的推进,江西旅游开发实施"聚湖实心"战略,既是改变江西旅游业现在的"空心离散格局"的需要,也是准确把握鄱湖旅游品牌新崛起的需要,而鄱阳湖生态经济区建设则将为江西旅游业的"聚湖实... 随着鄱阳湖生态经济区建设的推进,江西旅游开发实施"聚湖实心"战略,既是改变江西旅游业现在的"空心离散格局"的需要,也是准确把握鄱湖旅游品牌新崛起的需要,而鄱阳湖生态经济区建设则将为江西旅游业的"聚湖实心"战略实施奠定经济基础。旅游开发的"聚湖实心":一是准确定位江西旅游核心品牌亮点并转移开发重点;二是重点打造"鄱湖文明"核心景观区;三是着力建构"鄱湖文明"核心景观圈;四是以低碳旅游引领中国旅游新模式;五是提升南昌、九江、共青等旅游目的地集散中心和旅游服务中心的地位。"聚湖实心"开发战略的实施,将打破江西旅游业现有的"空心离散格局",刷新江西旅游品牌的主体形象;提升全省旅游业的管理水平;全面改变江西旅游目的地形象。 展开更多
关键词 江西旅游业 “聚湖实心” 开发战略
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Synthesis,Mechanical Characteristic and Near-infrared Reflective Property of Perylene Diimide-containing Polyurethane
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作者 SONG Yifan LI Zixin +7 位作者 TIAN Kaili BERMESHEV Maxim V HU Yanghao SU Yupeng WANG Jie PAN Hongfei LI He REN Xiangkui 《发光学报》 北大核心 2025年第7期1326-1332,共7页
Doping perylene diimide(PDI)into a polymer matrix is a simple strategy to prepare near-infrared(NIR)reflective materials,but the mechanical properties and NIR reflectance properties are significantly compromised due t... Doping perylene diimide(PDI)into a polymer matrix is a simple strategy to prepare near-infrared(NIR)reflective materials,but the mechanical properties and NIR reflectance properties are significantly compromised due to macro-phase separation.In this study,a novel polymer(denoted as PU-PDI)with intrinsic NIR reflective proper⁃ties was synthesized by covalent incorporation of PDI units into polyurethane chains.Its photophysical characteris⁃tics,mechanical property and NIR reflectance property are investigated in detail.The results show that covalent in⁃corporation reduces the severe aggregation of PDI units,thereby endows PU-PDI with excellent mechanical property.The elongation at break of PU-PDI can reach more than 700%,and the breaking strength is 34.11 MPa.Moreover,compared to the blending system,PU-PDI possesses enhanced NIR reflection ability due to the better dispersion of PDI units. 展开更多
关键词 perylene diimide POLYURETHANE near-infrared(NIR)reflectance
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Comparative study on the structural properties and electrochemical performance of xylan-derived char catalyzed by Na_(2)CO_(3) at various concentrations
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作者 LI Yamin GU Yue +1 位作者 WANG Shuang TAN Jun 《燃料化学学报(中英文)》 北大核心 2025年第5期638-645,共8页
In this study,the catalysis function of Na_(2)CO_(3) to the structural properties of xylan char was well investigated with Na_(2)CO_(3) on,and the electrochemical performance of xylan char as an anode material for sod... In this study,the catalysis function of Na_(2)CO_(3) to the structural properties of xylan char was well investigated with Na_(2)CO_(3) on,and the electrochemical performance of xylan char as an anode material for sodium-ion batteries was tested.The characterization of X-ray microscopy and scanning electron microscopy demonstrated that the morphological structure of xylan char was altered due to the addition of Na_(2)CO_(3) catalyst.The increasement of the Na_(2)CO_(3)/xylan ratio resulted in a slenderization of the triangular prism shape of the char skeleton and a reduction in porosity.X-ray diffraction analysis revealed that Na_(2)CO_(3) promoted the growth of the(004)crystal plane of graphite during xylan pyrolysis,while inhibiting the formation of the(100/101)crystal planes.Raman spectroscopy analysis indicated that the presence of Na_(2)CO_(3)had changed the graphitization degree of xylan char.Electrochemical tests further showed that char prepared with a Na_(2)CO_(3)/xylan mass ratio of 1∶1 exhibited the highest sodium storage capacity.This study provides a pathway for the rational design carbon materials derived from xylan for future applications in energy storage devices. 展开更多
关键词 xylan char alkali metal salts biomass CATALYSIS energy storage
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Fluorescent coordination polymers based on anthracene-and pyrene-derivative ligands
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作者 XI Jiming TENG Yukang +1 位作者 ZHANG Rui LU Zhenzhong 《无机化学学报》 北大核心 2025年第5期847-854,共8页
We report five coordination polymers(CPs)based on fluorescent ligands[1,6-di(1H-imidazol-1-yl)pyrene(dip),9,10-di(1H-imidazol-1-yl)anthracene(dia)]and anionic ligands[cyclohexane-1,4-dicarboxylic acid(H_(2)cda),campho... We report five coordination polymers(CPs)based on fluorescent ligands[1,6-di(1H-imidazol-1-yl)pyrene(dip),9,10-di(1H-imidazol-1-yl)anthracene(dia)]and anionic ligands[cyclohexane-1,4-dicarboxylic acid(H_(2)cda),camphoric acid(H_(2)cpa)].In[Cd(dip)(cda)]·4H_(2)O}_(n)(1),the Cd^(2+)ions,acting as tetrahedral nodes,are linked by dipand cda^(2-)ligands with four Cd^(2+)ions into five-fold interpenetrating network array of topology of dia.In{[Cd(dip)(cpa)]·4H_(2)O}_(n)(2),the Cd^(2+)ions,acting as a 4-connector,are linked by cpa^(2-)and dip ligands into a 3D framework ofcds topology.In{[Ni(dia)_(2)Cl_(2)]·DMF}_(n)(3),the Ni^(2+)ion is linked by four dia ligands into a layer structure,and 1Dchannels of a cross-section of 1.35 nm×0.96 nm are formed.In{[Cd(dia)_(2)(H_(2)O)_(2)](NO_(3))_(2)·2DMSO}n(4),the dia ligandsconnected Cd^(2+)ions into a 2D layer,and 1D channels are formed between adjacent layers with a cross-section of0.87 nm×0.43 nm.In[Zn(dip)Cl_(2)]_(n)(5),the Zn^(2+)ion is linked by dip ligands into an infinite 1D chain.The infrared,thermal gravimetric,and fluorescent emission data were collected and analyzed for these coordination polymers.CCDC:2356055,1;2440075,2;2356057,3;2356057,4;2356059,5. 展开更多
关键词 coordination polymer anthracene derivatives pyrene derivatives FLUORESCENCE
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A viologen-based Cd(Ⅱ)coordination polymer:Self-assembly,thermochromism,and electrochemical property
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作者 LI Xiaonan HAN Hui +3 位作者 ZHANG Yihan XIONG Jing GUO Tingting YAN Juanzhi 《无机化学学报》 北大核心 2025年第7期1439-1444,共6页
Under the condition of solvothermal synthesis,the viologen ligand 1,1′-bis(3-carboxyphenyl)-(4,4′-bipyri-dine)dichloride(H_(2)bcbpy·2Cl)and KI are coordinated with the metal cadmium ions.A case of thermochromic... Under the condition of solvothermal synthesis,the viologen ligand 1,1′-bis(3-carboxyphenyl)-(4,4′-bipyri-dine)dichloride(H_(2)bcbpy·2Cl)and KI are coordinated with the metal cadmium ions.A case of thermochromic coor-dination polymer[Cd(bcbpy)I_(2)]·2H_(2)O(1)was constructed.Complex 1 displays a 1D chain structure and exhibits thermochromic behavior.Under different temperature stimulation,the complex(ground)slowly changed from green to yellow-green,and with the increase of temperature,the color of complex 1 gradually deepened,and finally became orange-yellow.Therefore,complex 1 was prepared as a thermochromic film.In addition,we also performed electrochemical tests on complex 1,which showed that the complex is a semiconductor material.CCDC:2391802. 展开更多
关键词 coordination polymer VIOLOGEN THERMOCHROMISM electrochemical property
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A cadmium(Ⅱ)coordination polymer based on a semirigid tetracarboxylate ligand for highly selective detection of Fe^(3+)and 4-nitrophenol
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作者 BAI Yu WANG Jijiang +4 位作者 TANG Long YUE Erlin BAI Chao WANG Xiao ZHANG Yuqi 《无机化学学报》 北大核心 2025年第6期1217-1226,共10页
A novel coordination polymer(CP){[Cd_(2)(L)(1,4-bimb)_(1.5)(DMF)_(2)]·DMF}n(1)(H_(4)L=5,5'-[1,1'-biphenyl-4,4'-diylbis(oxy)]diisophthalic acid,1,4-bimb=1,4-bis(imidazole-1-ylmethyl)-benzene)has been d... A novel coordination polymer(CP){[Cd_(2)(L)(1,4-bimb)_(1.5)(DMF)_(2)]·DMF}n(1)(H_(4)L=5,5'-[1,1'-biphenyl-4,4'-diylbis(oxy)]diisophthalic acid,1,4-bimb=1,4-bis(imidazole-1-ylmethyl)-benzene)has been designed and synthesized through solvothermal reaction.Structural analysis shows that Cd(Ⅱ)is connected by H4L and 1,4-bimb to form a 2D network,and 1,4-bimb further expands the 2D network into a 3D framework.CP 1 can be used as an excellent fluorescence sensor for Fe^(3+)and 4-nitrophenol(4-NP),with low detection limits and good anti-interference.The detection limits of Fe^(3+)and 4-NP were 0.034 and 0.031μmol·L^(-1),respectively.In addition,the fluorescence quenching mechanism was studied.1 was successfully applied to determine Fe^(3+)and 4-NP content in the Yanhe River water sample.CCDC:2351092. 展开更多
关键词 coordination polymer Fe^(3+) 4-NITROPHENOL fluorescence sensing
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Three-Dimensional Melamine Carbon Sponge/NaI as Cathode Materials for Sodium-ion Batteries
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作者 Qian-Ying Huang Yue Liu +5 位作者 Zi-Xin Lin Shu-Yi Zheng Ting-Ting Mei Yu-Ting Tang Ying-He Zhang Jun Liu 《电化学(中英文)》 北大核心 2025年第5期62-69,共8页
The sodium-iodine(Na-I)battery exhibits significant potential as an alternative energy storage device to the lithium-ion battery.However,its development is hindered by inadequate electrical and thermal stability,as we... The sodium-iodine(Na-I)battery exhibits significant potential as an alternative energy storage device to the lithium-ion battery.However,its development is hindered by inadequate electrical and thermal stability,as well as the dissolution and shuttling of polyiodide.In this study,we report a preparation method for melamine carbon sponge(MC)via carbonizing a commercially available kitchen sponge.It was revealed that the as-prepared MC,composed of unique self-growing carbon nanotubes,could provide both physical and chemical adsorption capabilities for intermediate polyiodides to improve the electrochemical performance of NaI.Consequently,the NaI/MC electrode effectively minimized polyiodide dissolution and reduced the electrochemical impedance.The NaI/MC cathode demonstrated a high average discharge capacity of 92.75 mAh·g^(–1)over 200 cycles while maintaining a coulombic efficiency of 94%.The research findings from our study have promising applications in Na-I batteries. 展开更多
关键词 Sodium-iodine battery Sodium iodide Melamine carbon sponge
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Photocatalytic oxidation of high concentration NO over SnS_(2)/g-C_(3)N_(4): A mechanistic study
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作者 WANG Haocun ZHANG Qixin +2 位作者 YANG Yifan BIAN Junjie LI Chunhu 《燃料化学学报(中英文)》 北大核心 2025年第3期323-335,共13页
This study aims to enhance the photocatalytic performance of 2D/2D heterojunctions for NO removal from marine vessel effluents.SnS_(2)/g-C_(3)N_(4) composites were successfully constructed via a facile solvothermal me... This study aims to enhance the photocatalytic performance of 2D/2D heterojunctions for NO removal from marine vessel effluents.SnS_(2)/g-C_(3)N_(4) composites were successfully constructed via a facile solvothermal method,demonstrating a significant improvement in photocatalytic NO removal under visible light irradiation.For high-flux simulated flue gas,the composite with 10%SnS_(2)(denoted as SNCN-10)showed exceptional NO removal efficiency,reaching up to 66.8%,along with excellent reusability over five consecutive cycles.Detailed band structure and density of states(DOS)calculations confirmed the formation of a characteristic heterojunction.Spin-trapping ESR spectroscopy identified·O_(2)^(-)−as the key reactive species driving NO oxidation.Additionally,in situ DRIFT spectroscopy revealed that SNCN-10 facilitated the conversion of NO to nitrate through intermediate species,including bridging nitrite and cis-nitrite(N_(2)O_(2)^(2-)).Kinetic studies further indicated that NO oxidation followed the Langmuir-Hinshelwood(L-H)mechanism.Based on density functional theory(DFT)calculations of free energy changes,a comprehensive reaction pathway for NO oxidation was proposed.These findings provide valuable insights for the development of efficient photocatalytic strategies for NO removal. 展开更多
关键词 polymeric g-C_(3)N_(4) charge separation PHOTOCATALYSIS NO removal DFT calculations
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