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Electrical properties of fly ash and its decarbonization by electrostatic separation 被引量:10
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作者 Tao Youjun Ding Qingqing +3 位作者 Deng Mingrui Tao Dongping Wang Xu Zhang Jie 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2015年第4期629-633,共5页
The basic principle of fly ash triboelectrification is analysed. The mineral electrical index and test method are introduced. The electric difference of different mineral composition of fly ash is discussed by analysi... The basic principle of fly ash triboelectrification is analysed. The mineral electrical index and test method are introduced. The electric difference of different mineral composition of fly ash is discussed by analysis of chemical and mineral composition of fly ash in Xinwen power plant. The dielectric constant and charge-mass ratio of carbon and ash of fly ash are tested. Combined with the experimental study on rotary triboelectrostatic separation, the charged characteristic of fly ash particles with different size is gained. The results show that the dielectric constant of fly ash with different grain size decreased with the decrease of particle size, which lead to the poor electrical conductivity, Thus it can be seen that par- ticle size plays a leading role in conductivity, The charge of carbon and ash with each size increased with the decreased of particle size; and the charge-mass ratio between carbon and ash with the same size lar- ger with the decrease of size, which indicated that the finer particle size, the more favorable for triboelec- trification separation. In the same conditions, the best decarburization effect is realized when the particle size ranges from 0.038 to 0.074 ram, whose decarbonization rate and efficiency index reached 38.93% and 120.83% respectively. 展开更多
关键词 Fly ash Rotary triboelectrostatic separation Electrical property Decarbonization emciency
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SEPARATION PROPERTY OF POSITIVE RADIAL SOLUTIONS FOR A GENERAL SEMILINEAR ELLIPTIC EQUATION 被引量:3
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作者 杨芬 张丹丹 《Acta Mathematica Scientia》 SCIE CSCD 2011年第1期181-193,共13页
The asymptotic behavior at infinity and an estimate of positive radial solutions of the equation △u + sum from i=1 to k cirli upi = 0, x ∈ Rn,(0.1)are obtained and the structure of separation property of positive... The asymptotic behavior at infinity and an estimate of positive radial solutions of the equation △u + sum from i=1 to k cirli upi = 0, x ∈ Rn,(0.1)are obtained and the structure of separation property of positive radial solutions of Eq. (0.1) with different initial data α is discussed. 展开更多
关键词 Asymptotic behavior separation property semilinear elliptic equation
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In-situ incorporation of halloysite nanotubes with 2D zeolitic imidazolate framework-L based membrane for dye/salt separation
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作者 Yafei Su Xuke Zhang +2 位作者 Hui Li Donglai Peng Yatao Zhang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第6期103-111,共9页
Layered assembled membranes of 2D leaf-like zeolitic imidazolate frameworks(ZIF-L)nanosheets have received great attention in the field of water treatment due to the porous structure and excellent antibacterial abilit... Layered assembled membranes of 2D leaf-like zeolitic imidazolate frameworks(ZIF-L)nanosheets have received great attention in the field of water treatment due to the porous structure and excellent antibacterial ability,but the dense accumulation on the membrane surface and the low permeate flux greatly hinder their application.Herein,we synthesized m HNTs(modified halloysite nanotubes)/ZIF-L nanocomposites on modified m HNTs by in situ growth method.Interestingly,due to the different size of m HNTs and ZIF-L,m HNTs were packed in ZIF-L nanosheets.The hollow m HNTs provided additional transport channels for water molecules,and the accumulation of the ZIF-L nanosheets was decreased after assembling m HNTs/ZIF-L nanocomposites into membrane by filtration.The prepared m HNTs/ZIF-L membrane presented high permeate flux(59.6 L·m^(-2)·h^(-1)),which is 2-4 times of the ZIF-L membranes(14.8 L·m^(-2)·h^(-1)).Moreover,m HNTs/ZIF-L membranes are intrinsically antimicrobial,which exhibit extremely high bacterial resistance.We provide a controllable strategy to improve 2D ZIF-L assembles,and develops novel membranes using 2D package structure as building units. 展开更多
关键词 Zeolitic imidazolate framework Halloysite nanotubes 2D nanocomposites In-situ growth Dye/salt separation membrane Antibacterial property
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Efficient oil-water separation by novel biodegradable all cellulose composite filter paper
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作者 Chizhou Wang Shaodi Wu +4 位作者 Ning Zhang Zhaoli Jiang Xianglin Hou Long Huang Tiansheng Deng 《Green Energy & Environment》 SCIE EI CAS CSCD 2023年第6期1673-1682,共10页
Industrial production and domestic discharge produce a large amount of oily wastewater, which seriously affects the stability of the ecological environment. Membrane separation technology provides another path to trea... Industrial production and domestic discharge produce a large amount of oily wastewater, which seriously affects the stability of the ecological environment. Membrane separation technology provides another path to treating oily wastewater. And appropriate surface modification of the membrane helps to achieve high efficiency of treating oily wastewater. With green, economy and stability been more concerned.The focal research reports a completely biodegradable all cellulose composite filter paper(ACCFP) composed of Ⅰ-cellulose macrofibers and Ⅱ-cellulose matrix. It is a simple one-step impregnation method to adjust the surface microstructure of the pristine filter paper(PFP), and it does not involve with chemical reaction. The pre-wetted ACCFP consist of Ⅱ-cellulose hydrogel and Ⅰ-cellulose reinforcement in the process of oil-water separation. This layer of hydrogel is the fundamental to underwater superoleophobicity, which determines their eligibility for applications of efficient oil-water mixture or oil-in-water(oil/water) emulsion separation. The separation efficiency of oil-water mixture and oil/water emulsion exceed 95% and 99.9%, respectively. In addition, excellent mechanical properties of ACCFP in dry and wet conditions ensure its stability in service and prolong service life in applications. The focal study provides a new method for high-performance oil-water separation and it is more in line with sustainable chemistry. 展开更多
关键词 All cellulose composite filter paper Pristine filter paper Oil in water separation Underwater superoleophobic property
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Remarks on the Riesz Separation Property of the Linear Span of Positive Compact Operators 被引量:1
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作者 陈滋利 《Journal of Southwest Jiaotong University(English Edition)》 2005年第2期182-184,共3页
It is proven that there exists a Dedekind complete Banach lattice E such that the linear spans/f (E) and IV (E) of positive compact and positive weakly compact operators on E fails to possess the Riesz separation ... It is proven that there exists a Dedekind complete Banach lattice E such that the linear spans/f (E) and IV (E) of positive compact and positive weakly compact operators on E fails to possess the Riesz separation property. 展开更多
关键词 Banach lattice Dcdekind complete Compact operator Riesz separation property
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Photophysical Properties and Photovoltaic Performance of Sensitizers with a Bipyrimidine Acceptor
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作者 Shiling Liu Kun Gong +2 位作者 Wei Li Dongzhi Liu Xueqin Zhou 《Transactions of Tianjin University》 EI CAS 2024年第5期406-418,共13页
Molecular engineering is a crucial strategy for improving the photovoltaic performance of dye-sensitized solar cells(DSSCs). Despite the common use of the donor-π bridge-acceptor architecture in designing sensitizers... Molecular engineering is a crucial strategy for improving the photovoltaic performance of dye-sensitized solar cells(DSSCs). Despite the common use of the donor-π bridge-acceptor architecture in designing sensitizers, the underlying structure-performance relationship remains not fully understood. In this study, we synthesized and characterized three sensitizers: MOTP-Pyc, MOS_(2)P-Pyc, and MOTS_(2)P-Pyc, all featuring a bipyrimidine acceptor. Absorption spectra, cyclic voltammetry, and transient photoluminescence spectra reveal a photo-induced electron transfer(PET) process in the excited sensitizers. Electron spin resonance spectroscopy confirmed the presence of charge-separated states. The varying donor and π-bridge structures among the three sensitizers led to differences in their conjugation effect, influencing light absorption abilities and PET processes and ultimately impacting the photovoltaic performance. Among the synthesized sensitizers, MOTP-Pyc demonstrated a DSSC efficiency of 3.04%. Introducing an additional thienothiophene block into the π-bridge improved the DSSC efficiency to 4.47% for MOTS_(2)P-Pyc. Conversely, replacing the phenyl group with a thienothiophene block reduced DSSC efficiency to 2.14% for MOS_(2)P-Pyc. Given the proton-accepting ability of the bipyrimidine module, we treated the dye-sensitized TiO_(2) photoanodes with hydroiodic acid(HI), significantly broadening the light absorption range. This treatment greatly enhanced the short-circuit current density of DSSCs owing to the enhanced electron-withdrawing ability of the acceptor. Consequently, the HI-treated MOTS_(2)P-Pyc-based DSSCs achieved the highest power conversion efficiency of 7.12%, comparable to that of the N719 dye at 7.09%. This work reveals the positive role of bipyrimidine in the design of organic sensitizers for DSSC applications. 展开更多
关键词 Bipyrimidine acceptor Molecular engineering Photophysical processes Charge separation Dye-sensitized solar cells Acidichromic property
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The reform of mode idea of "separation of powers" for China's rural land property system
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作者 Xilong Deng Juan Chen 《International Journal of Technology Management》 2015年第8期136-139,共4页
By briefly reviewing the history of farmland property right in China, it puts forwards the conception of separation of three powers, which is to divide it into ownership, fight of contract, right of use, of farmland p... By briefly reviewing the history of farmland property right in China, it puts forwards the conception of separation of three powers, which is to divide it into ownership, fight of contract, right of use, of farmland property right. In addition, it specifies the practical operational methods to realize the reform that make peasants become the only owner of land in the category of public ownership. It expects to promote the communication and concentration of farmland, so that we can realize the industrialization of agriculture to promote the agricultural productivity level. 展开更多
关键词 FARMLAND property RIGHT separation of three POWERS REFORM CONCEPTION
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Shaping of metal-organic frameworks through a calcium alginate method towards ethylene/ethane separation 被引量:2
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作者 Jinlong Li Xiaoqing Wang +3 位作者 Puxu Liu Xiaohua Liu Libo Li Jinping Li 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2022年第2期17-24,共8页
The separation of ethylene and ethane is a crucial,challenging and cost-intensive process in chemical engineering.Metal-organic frameworks(MOFs)are a class of novel porous adsorbents used for the separation of ethylen... The separation of ethylene and ethane is a crucial,challenging and cost-intensive process in chemical engineering.Metal-organic frameworks(MOFs)are a class of novel porous adsorbents used for the separation of ethylene/ethane mixtures.However,MOFs are normally crystalline powders that cause multiple problems,such as dust,abrasion and heat/mass loss,as well as significant pressure drops on the adsorption bed resulting in a sudden stop in production.To solve these issues,we have prepared four different sphere-shaped adsorbents,including Mg-gallate,Co-gallate,MUV-10(Mn)and MIL-53(Al)using a calcium alginate method to achieve excellent ethylene/ethane separation performance.The performance of the sphere-shaped adsorbents has been validated using mechanical strength measurements,powder X-ray diffraction,scanning electron microscopy,thermogravimetric analysis,gas adsorption isotherms and dynamic breakthrough experiments.The excellent mechanical strength of these sphere-shaped adsorbents meets the criteria for industrial application in gas separation.Thus,the energy consumption and operating cost will be further reduced in the ethylene production process.We believe that this shaping method will open a prosperous route to the development of MOFs toward higher technology levels and their commercial application. 展开更多
关键词 Metal-organic frameworks Alginates SHAPING Mechanical properties ADSORPTION separation
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Effect of additives on growth of ferronickel grains and metal-slag separation behavior 被引量:1
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作者 Dong-lai MA Jian-bo ZHAO +4 位作者 Qing-qing HU Xue-ming LÜ Yang YOU Zhi-xiong YOU Xue-wei LÜ 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2022年第10期3459-3468,共10页
Na_(2)S,Na_(2)CO_(3),FeO,FeS and carbon were used to regulate the properties of slag or metal fractions,and their effects on metal growth and metal–slag separation behavior were investigated.The growth of ferronickel... Na_(2)S,Na_(2)CO_(3),FeO,FeS and carbon were used to regulate the properties of slag or metal fractions,and their effects on metal growth and metal–slag separation behavior were investigated.The growth of ferronickel grains can be enhanced by adding these additives,and Na_(2)S was the most effective.Na_(2)S,Na_(2)CO_(3) and FeO mainly affected the properties of slag,while carbon and FeS affected the metal fraction.The onset temperature of metal–slag separation was 1297℃ for the sample without additive,which was decreased to 1123 and 1101℃ after adding 3.30 wt.%Na_(2)S and 4.47 wt.%Na_(2)CO_(3),respectively.The onset temperature of metal–slag separation was mainly controlled by the slag fraction.The average apparent activation energy of metal grain growth was 125.32 kJ/mol without additive,and it decreased obviously after adding different additives.Na_(2)S also had the most remarkable effect on the decrease in activation energy. 展开更多
关键词 nickel laterite ore slag properties metal growth metal–slag separation kinetics
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Deep Eutectic Solvents: Green Solvents for Separation Applications 被引量:18
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作者 HOU Yucui YAO Congfei WU Weize 《物理化学学报》 SCIE CAS CSCD 北大核心 2018年第8期873-885,共13页
关键词 深共晶溶剂 化学物 氢键 化学分析
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Fiber swelling to improve cycle performance of paper-based separator for lithium-ion batteries application 被引量:2
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作者 Zhenghao Li Wei Wang +3 位作者 Xinmiao Liang Jianlin Wang Yonglin Xu Wei Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第4期92-100,共9页
It is well established that paper-based separators display short-circuit risk in lithium-ion batteries due to their intrinsic micron-sized pores.In this research,we have adjusted pore structure of paper by fiber swell... It is well established that paper-based separators display short-circuit risk in lithium-ion batteries due to their intrinsic micron-sized pores.In this research,we have adjusted pore structure of paper by fiber swelling in liquid electrolyte.Specifically,the paper-based separator is prepared by propionylated sisal fibers through a wet papermaking process.Scanning electron microscope(SEM)and multi-range X-ray nano-computed tomography(CT)images display strong swelling of modified fibers after electrolyte absorption,which can effectively decrease the pore size of separator.Due to the high electrolyte uptake(817 wt%),paper-based separator exhibits ionic conductivity of 2.93 mS cm^(-1).^(7)Li solid-state NMR spectroscopy and Gaussian simulation reveal that the formation of local high Li^(+)ion concentration in the separator and its low absorption energy with Li^(+) ion(62.2 kcal mol^(-1))is conducive to the ionic transportation.In particular,the assembled Li/separator/LiFePO_(4) cell displays wide electrochemical stability window(5.2 V)and excellent cycle performance(capacity retention of 96.6%after 100 cycles at 0.5C)due to the reduced side reactions as well as enhanced electrolyte absorption and retention capacity by propionylation.Our proposed strategy will provide a novel perspective to design high-performance biobased separators to boost the development of clean and sustainable energy economy. 展开更多
关键词 Paper-based separators Lithium-ion batteries Electrochemical properties Propionylation
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Three-in-one LaNiO_(3) functionalized separator boosting electrochemical stability and redox kinetics for high-performance Li-S battery 被引量:2
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作者 Weiyu Wang Mingxiu Hou +6 位作者 Fangqian Han Di Yu Jie Liu Qian Zhang Fengli Yu Lei Wang Maoshuai He 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第7期581-591,I0013,共12页
The lithium-sulfur(Li-S)battery,as one of the energy storage devices,has been in the limelight due to its high theoretical energy density.However,the poor redox kinetics and the"shuttle effect"of polysulfide... The lithium-sulfur(Li-S)battery,as one of the energy storage devices,has been in the limelight due to its high theoretical energy density.However,the poor redox kinetics and the"shuttle effect"of polysulfides severely restrict the use of Li-S batteries in practical applications.Herein,a novel bimetallic LaNiO_(3) functional material with high electrical conductivity and catalytic property is prepared to act as a high-efficiency polysulfide shuttling stopper.The three LaNiO_(3) samples with different physical/chemical characteristics are obtained by controlling the calcination temperature.In conjunction with the high electrical conductivity and excellent catalytic properties of the as-prepared materials,the appropriate chemisorption toward polysulfides offers great potential to enhance electrochemical stability for highperformance Li-S batteries.Particularly,the Li-S cell with the separator modified by such functional material gives a specific capacity of 658 mA h g^(-1) after 500 cycles at a high current density of 2 C.Even with high sulfur loading of 6.05 mg cm^(-2),the Li-S battery still exhibits an areal specific capacity of 2.81 m A h cm^(-2)after 150 cycles.This work paves a new avenue for the rational design of materials for separator modification in high-performance Li-S batteries. 展开更多
关键词 Li-S battery Functional separator Catalytic property Electrochemical stability Redox kinetics
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Amorphous-crystalline dual-layer structures resulting from metastable liquid phase separation in(Fe_(50)Co_(25)B_(15)Si_(10))_(80)Cu_(20) melt-spun ribbons
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作者 曹崇德 弓素莲 +4 位作者 郭晋波 宋瑞波 孙占波 杨森 王伟民 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第8期339-342,共4页
(Fe50Co25B15Si10)80Cu20 ribbons are prepared by using the single-roller melt-spinning method. A dual-layer structure consisting of a (Fe, Co)-rich amorphous phase and a Cu-rich crystalline phase forms due to metas... (Fe50Co25B15Si10)80Cu20 ribbons are prepared by using the single-roller melt-spinning method. A dual-layer structure consisting of a (Fe, Co)-rich amorphous phase and a Cu-rich crystalline phase forms due to metastable liquid phase separation before solidification. The magnetic hysteresis loops of the as-quenched and annealed samples are measured at room temperature. It is indicated that the coercivity of the ribbon is almost zero in the as-quenched state. The crystallization leads to the increase of coercivity and decrease of saturation magnetization. 展开更多
关键词 amorphous alloy rapid solidification liquid phase separation magnetic property
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Separation and purification of proteinases from Gastric Mucosa of Northern Sheatfish,Silurus soldatovi
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作者 刘伟 张秀梅 +1 位作者 战培荣 张照韩 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2011年第3期62-67,共6页
The separation and purification method for pepsin of Northern Sheatfish (Silurus soldatovi) was established by using the combination technology of salting-out,gel chromatography and gel electrophoresis,and the enzymic... The separation and purification method for pepsin of Northern Sheatfish (Silurus soldatovi) was established by using the combination technology of salting-out,gel chromatography and gel electrophoresis,and the enzymic properties were also analyzed.The experimental results indicated that 28% and 56% (NH4)2SO4 saturation could separate the activated protease from the pepsin extract of gastric mucosa of Sheatfish (Silurus soldatovi) ;compared with the homogenate extraction,the pepsin specific activity of purified extraction by Sephadex G-75 gel chromatography system increased 598 fold,was 5 times higher than that of activated liquid,and the total production rate was 10.1%.The purified pepsin liquor at the conditions of pH3.3 0.01 M alanine-formic acid buffering solution,60 cm chromatography column,and the flowing rate of 0.8 ML/min was analyzed by SDS-PAGE,which indicated that there were two bands and the molecular weight was 34.0 kDa and 40.4 kDa,respectively.There were two peaks in the enzyme activity determination of the separated collecting liquor in gel chromatography,and the SDS-PAGE showed the concentrations of the two proteins was different,which indicated that it existed at least two pepsins in the gastric mucosa of Sheatfish (Silurus soldatovi). 展开更多
关键词 Sheatfish (Silurus soldatovi) PEPSIN separation and purification property
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NIR-responsive Collagen-based Sponge Coated with Polydimethylsiloxane/Candle Soot for Oil-Water Separation
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作者 Min Zhang Chenchen Guo +6 位作者 Yu Wang Yunlong Zhang Hui Wu Liulian Huang Yonghao Ni Cuicui Ding Lihui Chen 《Paper And Biomaterials》 CAS 2022年第3期30-41,共12页
To fabricate an oil-water separation material that is rich in source,eco-friendly,and responsive,in this study,we successfully developed a collagen-based sponge for application to oil-water separation based on a green... To fabricate an oil-water separation material that is rich in source,eco-friendly,and responsive,in this study,we successfully developed a collagen-based sponge for application to oil-water separation based on a green and facile strategy.In this design,widely-available collagen(COL)was used as the substrate:it was immersed in polydimethylsiloxane(PDMS)suspension with candle soot(CS)nanoparticles,followed by hot curing.The resultant sponge(CS/PDMS-COL)possessed good hydrophobicity with a water contact angle of 148.3°under a low PDMS concentration of 2%.The results from field emission scanning electron microscope,Fourier transform infrared spectrometer,X-ray photoelectron spectrometer,and X-ray diffractometry demonstrated the successful coating of CS and PDMS on the surface of COL substrate.The CS/PDMS-COL can adsorb eight oils,with the adsorption capacity for trichloromethane reaching 95 g/g.With benzene as the target adsorbent,the separation efficiency was maintained at no less than 95%even after recycling 20 times.CS/PDMS-COL was also used to separate oil-in-water emulsion.Moreover,the sponge killed bacteria effectively due to its excellent near-infrared photothermal responsiveness.This study provides new insight into the preparation of facile oil-water separation materials based on naturally occurring biomaterials effortlessly. 展开更多
关键词 collagen sponge oil-water separation candle soot photothermal effect antibacterial property
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“三权分置”路径下数据产权客体的类型谱系 被引量:6
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作者 张素华 王年 《法治研究》 CSSCI 北大核心 2024年第2期47-60,共14页
“数据二十条”在表述数据产权“三权分置”时分别使用了“数据资源”“数据”“数据产品”三项表达来称谓“三权”的客体,从政策上肯认并确立了数据产权的客体对象。从法律视角审视,前述三项政策表达仍需经由学理阐释来论证其在法律上... “数据二十条”在表述数据产权“三权分置”时分别使用了“数据资源”“数据”“数据产品”三项表达来称谓“三权”的客体,从政策上肯认并确立了数据产权的客体对象。从法律视角审视,前述三项政策表达仍需经由学理阐释来论证其在法律上的定位及其相互关系,使之成为具有规范性的法律表达。“三权分置”路径下,“数据”的核心特征应包括信息属性、物理属性和集合属性,并在数据生产和流通使用的“价值链”上延展形成“数据资源”—“数据集合”—“数据产品”的类型层级。在分级分类构建原则下,作为产权客体的“数据”还可在横向上形成以公共数据与企业数据为一级子类型、公用/私用公共数据与公开/不公开企业数据为二级子类型的类型谱系。由此,便可在“三权分置”路径下阐明作为产权客体的数据的规范属性与类型谱系,为数据产权“三权分置”的法律化奠定基础和前提。 展开更多
关键词 数据产权 数据要素 三权分置 客体类型
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乙酰乙酸纤维素膜的手性传输性质研究
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作者 王涛 刘旭阳 +2 位作者 刘冬青 尤蒙 孟建强 《膜科学与技术》 CAS CSCD 北大核心 2024年第5期82-89,99,共9页
选用价格较低且易得的微晶纤维素作为实验原料,用酯交换法与乙酰乙酸叔丁酯反应,通过控制反应时间制备不同取代度的乙酰乙酸纤维素(CAA),并利用溶剂挥发法制得CAA膜.通过^(1)H NMR、FTIR、SEM和TGA等测试CAA膜的化学结构、形貌和热稳定... 选用价格较低且易得的微晶纤维素作为实验原料,用酯交换法与乙酰乙酸叔丁酯反应,通过控制反应时间制备不同取代度的乙酰乙酸纤维素(CAA),并利用溶剂挥发法制得CAA膜.通过^(1)H NMR、FTIR、SEM和TGA等测试CAA膜的化学结构、形貌和热稳定性.使用渗析器测试CAA膜对D,L-色氨酸的渗透拆分性质,利用二元高压梯度高效液相色谱测试渗透液中D-色氨酸和L-色氨酸的浓度.针对手性传输性质,研究了不同取代度的CAA膜对D,L-色氨酸的拆分机理.研究发现,低取代度的CAA膜有更好的手性拆分性能,而高取代度的CAA膜由于接触水溶液后自由体积增大,色氨酸容易通过渗透过膜,分离性能降低.经过对CAA膜对D-色氨酸和L-色氨酸的渗透、分配和扩散系数的分析可知,高取代度的CAA膜的手性拆分性能主要是由扩散控制.其中低取代度(DS=0.57)的CAA膜的对映体过量百分比在6 h内保持100%,超过6 h略微下降,之后趋于稳定.本研究通过简单的调控CAA的取代度制备了具有一定拆分性能的手性分离膜,为手性分离膜的设计提供了思路. 展开更多
关键词 手性分离 乙酰乙酸纤维素膜 酯交换反应 手性传输性质 D L-色氨酸
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数据三权分置制度释论:底层逻辑、法理反思与法律实现
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作者 高莉 《北京行政学院学报》 CSSCI 北大核心 2024年第6期76-87,共12页
数据产权分置涵括建立数据资源持有权、数据加工使用权、数据产品经营权分置的产权运行机制,这与数据从资源到要素再到产品的价值创造规律高度契合。尽管数据产权与数据财产权存在映射关系,但财产权所构筑的人为排他性,会增加数据流通... 数据产权分置涵括建立数据资源持有权、数据加工使用权、数据产品经营权分置的产权运行机制,这与数据从资源到要素再到产品的价值创造规律高度契合。尽管数据产权与数据财产权存在映射关系,但财产权所构筑的人为排他性,会增加数据流通和利用的成本,对数据价值实现产生相应影响,这也给数据产权分置政策转化为法律规范带来挑战。目前从数据主体视角出发形成的单一产权或二元权利结构,与“数据产权结构性分置”之政策意蕴和方向性策略不相一致。为此,要确保数据确权不偏离政策目标并实现“三权分置”的制度功能,就需要回归到数据客体视角,探索数据价值形态梯次变化的底层逻辑,破解既有数据确权研究中的理论困境,进而对数据资源持有权、数据加工使用权、数据产品经营权的配置提供必要的制度供给。 展开更多
关键词 数据产权分置 二元权利结构 开放式创新 公共物品理论
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农地产权的结构变化·权能功效和规模经营
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作者 何丹 吴九兴 《安徽农业科学》 CAS 2024年第5期251-254,共4页
运用文献研究法、对比分析法和制度分析法等研究方法,从产权结构角度阐释其变化历程和权能功效,进而揭示农地产权结构与农地经营模式的互馈。研究发现:农地产权结构的变化经历了所有权与使用权一体,所有权与使用权初步分离,所有权、资... 运用文献研究法、对比分析法和制度分析法等研究方法,从产权结构角度阐释其变化历程和权能功效,进而揭示农地产权结构与农地经营模式的互馈。研究发现:农地产权结构的变化经历了所有权与使用权一体,所有权与使用权初步分离,所有权、资格权及使用权再分离等发展阶段,权能划分越来越细、权能内涵界定更趋清晰。农地产权正持续进行合理性变革,农地权能的分解具有中国特色,更加注重农民权能利益保护,并与农地经营模式关联紧密。未来农地产权结构和农地经营模式的创新需要国家从政策措施、经济措施、法律措施等方面进一步完善和予以保障。 展开更多
关键词 农地产权 三权分置 农地经营 运行模式
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多离子印迹膜的制备及其吸附性能研究
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作者 祁迎春 王建 +3 位作者 董利林 陈妍妍 钟先保 刘勇 《延安大学学报(自然科学版)》 2024年第2期8-14,共7页
以Zn^(2+)、Co^(2+)、Cr^(3+)和Pb^(2+)为混合模板,双硫腙为螯合剂,APTES为功能单体,TEOS为交联剂,PVDF为基膜,采用凝胶溶胶法成功合成了对模板离子有高吸附量和良好特异性识别能力的多离子印迹膜(MIIM)。采用SEM对材料的形貌进行了表征... 以Zn^(2+)、Co^(2+)、Cr^(3+)和Pb^(2+)为混合模板,双硫腙为螯合剂,APTES为功能单体,TEOS为交联剂,PVDF为基膜,采用凝胶溶胶法成功合成了对模板离子有高吸附量和良好特异性识别能力的多离子印迹膜(MIIM)。采用SEM对材料的形貌进行了表征,并以多离子印迹聚合物(MIIP)为对比评价了MIIM的吸附性能。结果表明,MIIM对Zn^(2+)、Co^(2+)、Cr^(3+)和Pb^(2+)的吸附量分别是MIIP的1.71、1.43、1.60和9.03倍,最大吸附量分别为21.32、11.21、12.72和25.97 mg·g^(-1)。在竞争离子(Cu^(2+)、Ni^(2+)、Fe^(2+))存在的情况下具有良好的吸附选择性,MIIM的4种模板离子对Ni^(2+)和Fe^(2+)的特异性因子(SP)值在4.86~8.34之间,对Cu^(2+)的SP值在3.58~3.92之间。同时,MIIM可以多次再生,而不会明显降低吸附能力,在废水处理和样品前处理领域具有很好的应用前景。 展开更多
关键词 多离子印迹膜 重金属 吸附性能 选择性分离
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