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Generation of color-controllable room-temperature phosphorescence via luminescent center engineering and in-situ immobilization
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作者 Licheng Zheng Kai Jiang +3 位作者 Jiaren Du Yike Li Zhongjun Li Hengwei Lin 《Chinese Chemical Letters》 SCIE CAS CSCD 2023年第7期193-199,共7页
Materials with controllable luminescence colors are highly desirable for numerous promising applications, however, the preparation of such materials, particularly with color-controllable room-temperature phosphorescen... Materials with controllable luminescence colors are highly desirable for numerous promising applications, however, the preparation of such materials, particularly with color-controllable room-temperature phosphorescence(RTP), remains a formidable challenge. In this work, we reported on a facile strategy to prepare color-controllable RTP materials via the pyrolysis of a mixture containing 1-(2-hydroxyethyl)-urea(H-urea) and boric acid(BA). By controlling the pyrolysis temperatures, the as-prepared materials exhibited ultralong RTP with emission colors ranging from cyan, green, to yellow. Further studies revealed that multiple luminescent centers formed from H-urea, which were in-situ embedded in the B2O3matrix(produced from BA) during the pyrolysis process. The contents of the different luminescent centers could be regulated by the pyrolysis temperatures, resulting in color-tunable RTP. Significantly, the luminescent center engineering and in-situ immobilization strategy not only provided a facile method for conveniently preparing color-controllable RTP materials, but also endowed the materials prepared at relatively lower temperatures with color-changeable RTP features under thermal stimulus. Considering their unique properties, the potential applications of the as-obtained materials for advanced anti-counterfeiting and information encryption were preliminarily demonstrated. 展开更多
关键词 Carbon dots Room-temperature phosphorescence Luminescent center engineering in-situ immobilization ANTI-COUNTERFEITING Information security
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In-situ Leaching-immobilization of Lead in Soilvegetable System Based on Coupling of Remediation & Production
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作者 王莉玮 李燕燕 +2 位作者 代勇 杨志敏 陈玉成 《Agricultural Science & Technology》 CAS 2016年第9期2074-2077,2110,共5页
[Objective] The aim was to seek effective soil remediation technologies suitable for soils slightly or moderately polluted. [Method] In-situ leaching-immobi- lization was used to research remediation soil and vegetabl... [Objective] The aim was to seek effective soil remediation technologies suitable for soils slightly or moderately polluted. [Method] In-situ leaching-immobi- lization was used to research remediation soil and vegetable contaminated by lead in vegetable bases in Chongqing. [Result] By tartaric acid-based leaching-sodium sulphide-based immobilization, vegetable Pb reduction rate was 46.4%, soil Pb reduction rate was 8.45% and Pb immobilization rate was 9.3% in deeper horizons. EDTA leaching did reduce lead content in vegetables, but reduced vegetable yield simultaneously. [Conclusion] The coupling remediation technology brought heavy metal contents down in vegetables without affecting productions. Therefore, it guarantees vegetable safety and reduces vegetable farmer's economic loss. It is a remediation technology suitable for soils slightly or moderately contaminated by heavy metals. 展开更多
关键词 VEGETABLES SOILS LEAD LEACHING immobilization
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Optical biosensing of monkeypox virus using novel recombinant silica-binding proteins for site-directed antibody immobilization
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作者 Xixi Song Ying Tao +1 位作者 Sumin Bian Mohamad Sawan 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2024年第10期1496-1504,共9页
The efficient immobilization of capture antibodies is crucial for timely pathogen detection during global pandemic outbreaks.Therefore,we proposed a silica-binding protein featuring core functional domains(cSP).It com... The efficient immobilization of capture antibodies is crucial for timely pathogen detection during global pandemic outbreaks.Therefore,we proposed a silica-binding protein featuring core functional domains(cSP).It comprises a peptide with a silica-binding tag designed to adhere to silica surfaces and tandem protein G fragments(2C2)for effective antibody capture.This innovation facilitates precise site-directed immobilization of antibodies onto silica surfaces.We applied cSP to silica-coated optical fibers,creating a fiber-optic biolayer interferometer(FO-BLI)biosensor capable of monitoring the monkeypox virus(MPXV)protein A29L in spiked clinical samples to rapidly detect the MPXV.The cSP-based FO-BLI biosensor for MPXV demonstrated a limit of detection(LOD)of 0.62 ng/mL in buffer,comparable to the 0.52 ng/mL LOD achieved using a conventional streptavidin(SA)-based FO-BLI biosensor.Furthermore,it achieved LODs of 0.77 ng/mL in spiked serum and 0.80 ng/mL in spiked saliva,exhibiting no cross-reactivity with other viral antigens.The MPXV detection process was completed within 14 min.We further proposed a cSP-based multi-virus biosensor strategy capable of detecting various pandemic strains,such as MPXV,the latest coronavirus disease(COVID)variants,and influenza A protein,to extend its versatility.The proposed cSP-modified FO-BLI biosensor has a high potential for rapidly and accurately detecting MPXV antigens,making valuable contributions to epidemiological studies. 展开更多
关键词 Site-directed immobilization Silica-binding proteins Optical biosensing Monkeypox virus Spiked clinical samples Multi-virus biosensor
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Changes in calcium accumulation and utilization efficiency and their impact on recycling,immobilization,and export across the oil palm cycle
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作者 Ismael de Jesus Matos Viégas Luma Castro de Souza +4 位作者 Eric Victor de Oliveira Ferreira Milton Garcia Costa Glauco André dos Santos Nogueira Vitor Resende do Nascimento Candido Ferreira de Oliveira Neto 《Oil Crop Science》 CSCD 2024年第3期143-150,共8页
Effective calcium(Ca)management is crucial for optimizing oil palm cultivation and enhancing crop yield.This study aimed to gain insights into the dynamics of Ca concentration,accumulation,exportation,immobilization,a... Effective calcium(Ca)management is crucial for optimizing oil palm cultivation and enhancing crop yield.This study aimed to gain insights into the dynamics of Ca concentration,accumulation,exportation,immobilization,and recycling in various oil palm organs relative to plant age.The experiment was conducted at the Agropalma enterprise site in the northeastern region of Para State,Brazil,evaluating seven plant age treatments:2,3,4,5,6,7,and 8 years old.Employing a completely randomized design with four replications.The results demonstrated an age-related increase in Ca concentration in petioles,rachis,arrows,male inflorescences,peduncles,and fruits.Furthermore,Ca accumulation exhibited an upward trend in all organs with progressing plant age.Notably,the study revealed an enhanced Ca use efficiency across all plant organs in correlation with the age of oil palm cultivation.These findings underscore the dynamic nutritional demands of oil palm,influencing Ca immobilization,cycling,and export throughout its developmental stages. 展开更多
关键词 Elaeis guineensis Jacq Ca cycling Ca export Ca immobilization Ca use efficiency Plant nutrition AMAZON
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Overview of in-situ oxygen production technologies for lunar resources
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作者 Youpeng Xu Sheng Pang +5 位作者 Liangwei Cong Guoyu Qian Dong Wang Laishi Li Yusheng Wu Zhi Wang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第2期233-255,共23页
The rich resources and unique environment of the Moon make it an ideal location for human expansion and the utilization of extraterrestrial resources.Oxygen,crucial for supporting human life on the Moon,can be extract... The rich resources and unique environment of the Moon make it an ideal location for human expansion and the utilization of extraterrestrial resources.Oxygen,crucial for supporting human life on the Moon,can be extracted from lunar regolith,which is highly rich in oxygen and contains polymetallic oxides.This oxygen and metal extraction can be achieved using existing metallurgical techniques.Furthermore,the ample reserves of water ice on the Moon offer another means for oxygen production.This paper offers a detailed overview of the leading technologies for achieving oxygen production on the Moon,drawing from an analysis of lunar resources and environmental conditions.It delves into the principles,processes,advantages,and drawbacks of water-ice electrolysis,two-step oxygen production from lunar regolith,and one-step oxygen production from lunar regolith.The two-step methods involve hydrogen reduction,carbothermal reduction,and hydrometallurgy,while the one-step methods encompass fluorination/chlorination,high-temperature decomposition,molten salt electrolysis,and molten regolith electrolysis(MOE).Following a thorough comparison of raw materials,equipment,technology,and economic viability,MOE is identified as the most promising approach for future in-situ oxygen production on the Moon.Considering the corrosion characteristics of molten lunar regolith at high temperatures,along with the Moon's low-gravity environment,the development of inexpensive and stable inert anodes and electrolysis devices that can easily collect oxygen is critical for promoting MOE technology on the Moon.This review significantly contributes to our understanding of in-situ oxygen production technologies on the Moon and supports upcoming lunar exploration initiatives. 展开更多
关键词 lunar resources in-situ oxygen production space metallurgy molten lunar regolith electrolysis
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Multiphysics simulation and optimization of the in-situ beneficiation process of ilmenite minerals from lunar regolith
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作者 Peng ZHANG Xin LIU +11 位作者 Guanghui LIU Wei DAI Hanzhe YANG Haibo ZHENG Zhi WANG Ran NIU Yifan BAI Yang ZHANG Chengbao LIU Ge YANG Junwei YANG Guang ZHANG 《Science China Earth Sciences》 2025年第1期195-207,共13页
The exploration and utilization of lunar resources have become the major objectives of future lunar exploration missions.The classified collection and processing of lunar minerals is the basic prerequisite for the in-... The exploration and utilization of lunar resources have become the major objectives of future lunar exploration missions.The classified collection and processing of lunar minerals is the basic prerequisite for the in-situ exploration and utilization of lunar resources.In this study,we propose a scheme for in-situ separation of magnetic minerals from lunar soils using the dry magnetic separation method.The scheme can realize the purpose of separating magnetic minerals from lunar regolith by altering the motion trajectory of lunar regolith particles with different magnetic properties.Detailed modeling of the dry magnetic separation device is conducted,and the three-dimensional distribution of magnetic parameters is calculated and analyzed.Based on the characterization and analysis of the Chang E-5's samples,the morphologies and physical parameters of lunar regolith particles are modeled and simulated.A discrete element simulation of the motion process of lunar regolith particles under multi-physical field conditions is performed,and the influences of key parameters on the beneficiation performance of lunar magnetic minerals are investigated.Our results indicate that optimal separation and beneficiation of lunar regolith particles can be achieved under specific conditions of magnetic field strength and drum speed.Additionally,we analyze the effects of lunar weak gravity conditions and the charged nature of lunar particles on the beneficiation process,showing that these factors can obviously enhance the beneficiation process of lunar ilmenites.This study demonstrates the feasibility of using the dry magnetic separation method for the beneficiation of magnetic minerals from lunar regolith,providing a theoretical basis for the scientific tasks of collecting,processing,and utilizing lunar mineral resources. 展开更多
关键词 Lunar regolith in-situ resource utilization Magnetic separation Classified sampling
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Multiple-stage W mineralization in the Guanfang W deposit,southeastern Yunnan Province,China:Insights from scheelite in-situ trace elemental and Sr isotopic analyses
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作者 Bin Sun Yi Liu +4 位作者 Zhigang Kong Xuelong Liu Xiaojun Jiang Chao Li Wenchang Li 《Acta Geochimica》 2025年第1期112-127,共16页
The Guanfang large-scale W deposit is located in the W polymetallic ore concentration area of Bozhushan in southeastern Yunnan,China.Despite extensive research,the fluid evolution process of the deposit remains ambigu... The Guanfang large-scale W deposit is located in the W polymetallic ore concentration area of Bozhushan in southeastern Yunnan,China.Despite extensive research,the fluid evolution process of the deposit remains ambiguous,leading to controversy regarding its genesis.This study conducted a detailed field geological survey,with systematic sampling of the KT6 orebody,to delineate mineralization stages.Fine mineralogy work,including the use of CL images of scheelite,in-situ LA-ICP-MS trace elements,and Sr isotopes,was carried out on diff erent generations of scheelite formed in various stages.The findings identified the evolution of fluids in the mineralization process,shedding light on the genesis of the deposit.The study revealed four mineralization stages at the Guanfang W deposit:prograde skarn stage,retrograde skarn stage,quartz-sulfide stage,and carbonate-fluorite stage.Diff erent generations of scheelite(Sch I,Sch II,Sch III)were observed in the first three stages,displaying distinct chondrite-normalized REE patterns.The REE of Sch I mainly substituted into the Ca site by REE^(3+)+□_(Ca),and there may be a similar substitution of Nb for REE,whereas it is not the main substitution method.The REE of Sch II mainly enter the scheelite lattice in the form of REE 3++Na+,and there may be a substitution of Nb for REE isomorphism.In the early stage,The REE of Sch III was mainly replaced by Nb for REE isomorphism,while in the later stage,the replacement mode of REE^(3+)+□_(Ca)coexisted with it.The Mo content in scheelite,along with the corresponding Eu anomalies in both scheelite and garnet,collectively imply that the ore-forming fluids during various mineralization stages were predominantly oxidizing,with only slight reducibility observed in Sch II.The in-situ Sr isotope ratios of scheelite concentrates ranged from 0.7093 to 0.7153,resembling those of the Bozhushan granite,indicating a relationship between W mineralization and granite.In addition,the Y/Ho ratios of scheelite from various mineralization stages exhibit a narrow range(19-31),with a pronounced correlation between the contents of Y and Ho and a similar trend in their variation.This consistency suggests that the Guanfang deposit has undergone a uniform or comparable evolutionary process,implying a stable ore-forming fluid across diff erent mineralization stages. 展开更多
关键词 Guanfang W deposit Trace elements of scheelite in-situ Sr isotopes Southeast Yunnan
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Immobilization of activated sludge using improved polyvinyl alcohol (PVA) gel 被引量:35
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作者 ZHANG Li-sheng WU Wei-zhong WANG Jian-long 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2007年第11期1293-1297,共5页
The microbial immobilization method using polyvinyl alcohol (PVA) gel as an immobilizing material was improved and used for entrapment of activated sludge. The oxygen uptake rate (OUR) was used to characterize the... The microbial immobilization method using polyvinyl alcohol (PVA) gel as an immobilizing material was improved and used for entrapment of activated sludge. The oxygen uptake rate (OUR) was used to characterize the biological activity of immobilized activated sludge. Three kinds of PVA-immobilized particles of activated sludge, that is, PVA-boric acid beads, PVA-sodium nitrate beads and PVA-orthophosphate beads were prepared, and their biological activity was compared by measuring the OUR value. The bioactivity of both autotrophic and heterotrophic microorganisms of activated sludge was determined using different synthetic wastewater media (containing 250 mg/L COD and 25 mg/L NH4^+ -N). The experimental results showed that the bioactivity and stability of the three kinds of immobilized activated sludge was greatly improved after activation. With respect of the bioactivity and the mechanical stability, the PVA-orthophosphate method may be a promising and economical technique for microbial immobilization. 展开更多
关键词 immobilization biological activity oxygen uptake rate (OUR) polyvinyl alcohol (PVA)
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Immobilization study of biosorption of heavy metal ions onto activated sludge 被引量:14
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作者 WUHai-suo ZHANGAi-qiang WANGLian-sheng 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2004年第4期640-645,共6页
Activated sludge was immobilized into Ca-alginate beads via entrapment, and biosorption of three heavy metal ions, copper(Ⅱ), zinc(Ⅱ), and chromimum(Ⅱ), from aqueous solution in the concentration range of 10\_100 m... Activated sludge was immobilized into Ca-alginate beads via entrapment, and biosorption of three heavy metal ions, copper(Ⅱ), zinc(Ⅱ), and chromimum(Ⅱ), from aqueous solution in the concentration range of 10\_100 mg/L was studied by using both entrapped activated sludge and inactivated free biomass at pH≤5. A biphasic metal adsorption pattern was observed in all immobilized biomass experiments. The biosorption of metal ions by the biosorbents increased with the initial concentration increased in the medium. The adsorption rate of immobilized pre-treated activated sludge(PAS) was much lower than that of free PAS due to the increase in mass transfer resistance resulting from the polymeric matrix. Biosorption equilibrium of beads was established in about 20 h and the adsorbed heavy metal ions did not change further with time. No significant effect of temperature was observed in the test for free biomass while immobilized PAS appeared to be strong temperature dependent in the test range of 10 and 40℃. Besides, the content of activated sludge in the calcium alginate bead has an influence on the uptake of heavy metals. The sorption equilibrium was well modeled by Langmuir isotherm, implying monomolecular adsorption mechanism. Carboxyl group in cell wall played an important role in surface adsorption of heavy metal ions on PAS. 展开更多
关键词 BIOSORPTION alginate beads immobilization heavy metal activated sludge wastewater treatment
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Immobilization of organophosphorus hydrolase enzyme by covalent attachment on modified cellulose microfibers using different chemical activation strategies:Characterization and stability studies 被引量:5
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作者 Meisam Sharifi Seyed-Mortaza Robatjazi +1 位作者 Minoo Sadri Jafar Mohammadian Mosaabadi 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第1期191-199,共9页
The plant cellulose powder was activated by two different methods using 1,4-butanediol diglycidyl ether(BTDE)and 1,1′-Carbonyldiimidazole(CDI) as the chemical coupling agents.Organophosphorus hydrolase(OPH) from Flav... The plant cellulose powder was activated by two different methods using 1,4-butanediol diglycidyl ether(BTDE)and 1,1′-Carbonyldiimidazole(CDI) as the chemical coupling agents.Organophosphorus hydrolase(OPH) from Flavobacterium ATCC 27551 was immobilized on any of activated support through covalent bonding.The optimal conditions of affecting parameters on enzyme immobilization in both methods were found, and it was demonstrated that the highest activity yields of immobilized OPH onto epoxy and CDI treated cellulose were 68.32%and 73.51%, respectively.The surface treatment of cellulose via covalent coupling with BTDE and CDI agents was proved by FTIR analysis.The kinetic constants of the free and immobilized enzymes were determined, and it was showed that both immobilization techniques moderately increased the Kmvalue of the free OPH.The improvements in storage and thermal stability were investigated and depicted that the half-life of immobilized OPH over the surface of epoxy modified cellulose had a better growth compared to the free and immobilized enzymes onto CDI treated support.Also, the pH stability of the immobilized preparations was enhanced relative to the free counterpart and revealed that all enzyme samples would have the same optimum pH value for stability at 9.0.Additionally, the immobilized OPH onto epoxy and CDI activated cellulose retained about 59% and 68% of their initial activity after ten turns of batch operation, respectively.The results demonstrated the high performance of OPH enzyme in immobilized state onto an inexpensive support with the potential of industrial applications. 展开更多
关键词 ORGANOPHOSPHORUS HYDROLASE CELLULOSE powder Activation immobilization Stability
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Human sperm immobilization effect of Carica papaya seed extracts: an in vitro study 被引量:6
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作者 Nirmal K Lohiya Lalit K Kothari +2 位作者 B Manivannan Pradyumna K Mishra Neelam Pathak 《Asian Journal of Andrology》 SCIE CAS CSCD 2000年第2期103-109,共7页
Aim: To examine if the seed extracts of Carica papaya, which showed anfispermatogenic/sperm immobilizationproperties in animal models, could cause human sperm immobilization in vitro. Methods: Chloroform extract, ben-... Aim: To examine if the seed extracts of Carica papaya, which showed anfispermatogenic/sperm immobilizationproperties in animal models, could cause human sperm immobilization in vitro. Methods: Chloroform extract, ben-zene chromatographic fraction of the chloroform extract, its methanol and ethyl acetate sub-fractions and the isolatedcompounds from the sub-fractions i. e., ECP 1 & 2 and MCP 1 & 2, of the seeds of Carica papaya were used at con-centrations of 0.1%, 0.5%, 1% and 2%. Sperm motility was assessed immediately after addition of extracts and ev-ery 5 minutes thereafter for 30 minutes. Results: There were dose-dependent spermicidal effects showing an instantfall in the sperm motility to less than 20% at 2% concentration. Isolated compounds ECP 1 & 2 were more effective in-ducing a motility of less than 10%. Many of the spermatozoa became vibratory on the spot. Total inhibition of motilitywas observed within 20-25 rain at all concentrations of all products. Scanning and transmission electron microscopyrevealed deleterious changes in the plasma membrane of the head and mid-piece of spermatozoa. Sperm viability testand the number of abnormal spermatozoa after completion of incubation suggested that the spermatozoa were infertile.The effects were spermicidal but not spermiostatic as revealed by the sperm revival test. Conclusion: The results re-veal spermicidal activity in vitro of the seed extracts of Carica papaya. 展开更多
关键词 human sperm sperm immobilization spermicidal agents Carica papaya
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Inhibition of acid mine drainage and immobilization of heavy metals from copper flotation tailings using a marble cutting waste 被引量:7
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作者 Gulsen Tozsin 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2016年第1期1-6,共6页
Acid mine drainage (AMD) with high concentrations of sulfates and metals is generated by the oxidation of sulfide beating wastes. CaCO3-rich marble cutting waste is a residual material produced by the cutting and po... Acid mine drainage (AMD) with high concentrations of sulfates and metals is generated by the oxidation of sulfide beating wastes. CaCO3-rich marble cutting waste is a residual material produced by the cutting and polishing of marble stone. In this study, the feasibility of using the marble cutting waste as an acid-neutralizing agent to inhibit AMD and immobilize heavy metals from copper flotation tailings (sul- fide-beating wastes) was investigated. Continuous-stirring shake-flask tests were conducted for 40 d, and the pH value, sulfate content, and dissolved metal content of the leachate were analyzed every 10 d to determine the effectiveness of the marble cutting waste as an acid neu- tralizer. For comparison, CaCO3 was also used as a neutralizing agent. The average pH value of the leachate was 2.1 at the beginning of the experiment (t = 0). In the experiment employing the marble cutting waste, the pH value of the leachate changed from 6.5 to 7.8, and the sul- fate and iron concentrations decreased from 4558 to 838 mg/L and from 536 to 0.01 mg/L, respectively, after 40 d. The marble cutting waste also removed more than 80wt% of heavy metals (Cd, Cr, Cu, Ni, Pb, and Zn) from AMD generated by copper flotation tailings. 展开更多
关键词 acid mine drainage heavy metals copper ore treatment TAILINGS MARBLE immobilization
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Preparation of Magnetic Chitosan Nanoparticles and Immobilization of Laccase 被引量:5
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作者 方华 黄俊 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2009年第1期42-47,共6页
The magnetic chitosan nanoparticles were prepared by reversed-phase suspension method using Span-80 as an emulsifier, glutaraldehyde as cross-linking reagent. And the nanoparticles were characterized by TEM, FT-IR and... The magnetic chitosan nanoparticles were prepared by reversed-phase suspension method using Span-80 as an emulsifier, glutaraldehyde as cross-linking reagent. And the nanoparticles were characterized by TEM, FT-IR and hysteresis loop. The results show that the nanoparticles are spherical and almost superparamagnetic. The laccase was immobilized on nanoparticles by adsorption and subsequently by cross-linking with glutaraldehyde. The immobilization conditions and charac-terizations of the immobilized laccase were investigated. The optimal immobilization conditions were as follows: 10 mL of phosphate buffer (0.1 M, pH 7.0) containing 50 mg of magnetic chitosan nanoparticles, 1.0 mg·mL-1 of laccase and 1% (v/v) glutaraldehyde, immobilization temperature of 4 ℃ and immobilization time of 4 h. The immobilized laccase exhibited an appreciable catalytic capability (480 units·g-1 support) and had good storage stability and operation stability. The Km of immobilized and free laccase for ABTS were 140.6 and 31.1 μM in phosphate buffer (0.1 M, pH 3.0) at 37 ℃, respectively. The immobilized laccase is a good candidate for the research and development of biosensors based on laccase catalysis. 展开更多
关键词 LACCASE magnetic chitosan nanoparticles immobilization enzyme activity STABILITY
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Synthesis and Heavy Metal Immobilization Behaviors of Fly Ash based Gepolymer 被引量:4
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作者 张云升 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2009年第5期819-825,共7页
Two aspects of studies were carried out: 1) synthesis of geopolymer by using fly ash and metakaolin; 2) Immobilization behaviors of fly ash based geopolymer in a presence of Pb and Cu ions. As for the synthesis of ... Two aspects of studies were carried out: 1) synthesis of geopolymer by using fly ash and metakaolin; 2) Immobilization behaviors of fly ash based geopolymer in a presence of Pb and Cu ions. As for the synthesis of fly ash based geopolymer, 4 different fly ash content (10%, 30%, 50%, 70%) and 3 types of curing regimes (standard curing, steam curing and autoclave curing) were investigated to obtain the optimum synthesis condition based on the compressive and flexural strength. The experimental results show that geopolymer, containing 30% fly ash and synthesized at steam curing (80 ℃ for 8 h), exhibits higher mechanical strengths. The compressive and flexural strengths of fly ash based geopolymer reach 32.2 MPa and 7.15 MPa, respectively. Additionally, Infrared (IR) and X-ray diffraction (XRD) techniques were used to characterize the microstructure of the fly ash geopolymer. IR spectra shows that the absorptive band at 1086 cm^-1 shifts to lower wave number around 1033 cm^-1, and the 6-coordinated Al transforms into 4-coordination during the syn-thesis of fly ash based geopolymer. The resulting geopolymeric products were X-ray amorphous materials. As for immobilization of heavy metals, the leaching tests were employed to investigate the immobilization behaviors of the fly ash based geopolymer synthesized under the above optimum condition. The leaching tests showed that fly ash based geopolymer can effectively immobilize Cu and Pb heavy metal ions, and the immobilization efficiency reached 90% greater when heavy metals were incorporated in the fly ash geopolymer in the range of 0.1% to 0.3%. The Pb exhibits better immobilization efficiency than the Cu, especially in the case of large dosages of heavy metals. 展开更多
关键词 GEOPOLYMER fly ash SYNTHESIS immobilization heavy metals
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Surface Modification of Polypropylene Microporous Membrane by Atmospheric-Pressure Plasma Immobilization of N,N-dimethylamino Ethyl Methacrylate 被引量:3
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作者 钟少锋 《Plasma Science and Technology》 SCIE EI CAS CSCD 2010年第5期619-627,共9页
Surface modification of polypropylene microporous membrane (PPMM) was performed by atmospheric pressure dielectric barrier discharge plasma immobilization of N,Ndimethylamino ethyl methacrylate (DMAEMA). Structura... Surface modification of polypropylene microporous membrane (PPMM) was performed by atmospheric pressure dielectric barrier discharge plasma immobilization of N,Ndimethylamino ethyl methacrylate (DMAEMA). Structural and morphological changes on the membrane surface were characterized by attenuated total reflection-Fourier transform infrared spectroscopy (FT-IR/ATR), X-ray photoelectron spectroscope (XPS) and field emission scanning electron microscopy (FE-SEM). Water contact angles of the membrane surfaces were also measured by the sessile drop method. Results reveal that both the plasma-treating conditions and the adsorbed DMAEMA amount have remarkable effects on the immobilization degree of DMAEMA. Peroxide determination by 1,1-diphenyl-2-picrvlhydrazyl (DPPH) method verifies the exsistence of radicals induced by plasma, which activize the immobilization reaction. Pure water contact angle on the membrane surface decreased with the increase of DMAEMA immobilization degree, which indicates an enhanced hydrophilicity for the modified membranes. The effects of immobilization degrees on pure water fluxes were also measured. It is shown that pure water fluxes first increased with immobilization degree and then decreased. Finally, permeation of bovine serum albumin (BSA) and lysozyme solution were measured to evaluate the antifouling property of the DMAEMA-modified membranes, from which it is shown that both hydrophilicity and electrostatic repulsion are beneficial for membrane antifouling. 展开更多
关键词 polypropylene microporous membrane DMAEMA atmospheric-pressureplasma immobilization ANTIFOULING
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Sperm immobilization activity of Allium sativum L. and other plant extracts 被引量:4
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作者 Kausiki Chakrabarti Sulagna Pal Asok K.Bhattacharyya 《Asian Journal of Andrology》 SCIE CAS CSCD 2003年第2期131-135,共5页
<abstract>Aim: To identify possible spermicidal agents through screening a number of edible medicinal plants with antimicrobial activity. Methods: Initial screening was made on the basis of ram cauda epididymal ... <abstract>Aim: To identify possible spermicidal agents through screening a number of edible medicinal plants with antimicrobial activity. Methods: Initial screening was made on the basis of ram cauda epididymal sperm immobilization immediately after addition of extracts. The most potent extract was selected and was evaluated on both ram and human spermatozoa. To unravel its mode of action several sperm functional tests were carried out, namely viability of cells, hypo-osmotic swelling test for membrane integrity and assays of membrane-bound enzyme 5'-nucleotidase and acrosomal marker enzyme acrosin. Results: The crude aqueous extract of the bulb of Allium sativum L. showed the most promising results by instant immobilization of the ram epididymal sperm at 0.25 g/mL and human ejaculated sperm at 0.5 g/mL. Sperm immobilizing effects were irreversible and the factor of the extract responsible for immobilization was thermostable up to 90 癈. On boiling at 100 癈 for 10 minutes, this activity was markedly reduced. Moreover, this extract was able to cause aggregation of ram sperms into small clusters after 30 minutes of incubation at 37 癈. However this property was not found in human spermatozoa. More than 50 % reduction in sperm viability and hypo-osmotic swelling occurred in treated sperm as compared with the controls, indicating the possibility of plasma membrane disintegration which was further supported by the significant reduction in the activity of membrane bound 5'-nucleotidase and acrosomal acrosin. Conclusion: The crude aqueous extract of A. sativum bulb possesses spermicidal activity in vitro. 展开更多
关键词 Allium sativum plant extracts SPERM immobilization farm animals RAM human spermicidal agents thermostability
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Immobilization of microorganisms using carrageenan gels coated with chitosan and application to biodegradation of 4-chlorophenol 被引量:2
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作者 Wang Jianlong Li Ping +2 位作者 Shi Hanchang Qian Yi China Zhou Ding 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1997年第3期30-34,共5页
A new cell immobilization method based on the replacement of KCl by KCl+chitosan as the gelling agent was developed. The experimental results showed that through addition of chitosan into gelling agent, the mechanica... A new cell immobilization method based on the replacement of KCl by KCl+chitosan as the gelling agent was developed. The experimental results showed that through addition of chitosan into gelling agent, the mechanical strength and the thermal stability of the carrageenan gel were greatly improved. The new immobilization method was used to entrap a chlorophenol degrading microorganism. The immobilized microbial cells were applied for chlorophenol biodegradation. The experiments demonstrated that immobilized cells exhibit a higher bioactivity in the degradation of chlorophenol than free cells. 展开更多
关键词 CARRAGEENAN CHITOSAN immobilization 4 chlorophenol biodegradation.
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Neuropeptide Y and leptin receptor expression in the hypothalamus of rats with chronic immobilization stress 被引量:6
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作者 Shaoxian Wang Jiaxu Chen +3 位作者 Guangxin Yue Minghua Bai Meijing Kou Zhongye Jin 《Neural Regeneration Research》 SCIE CAS CSCD 2013年第18期1721-1726,共6页
In this study, Sprague-Dawley rats were immobilized to a frame for 3 hours a day for 21 days to establish a model of chronic immobilization stress. The body weight and food intake of rats subjected to chronic immobili... In this study, Sprague-Dawley rats were immobilized to a frame for 3 hours a day for 21 days to establish a model of chronic immobilization stress. The body weight and food intake of rats subjected to chronic immobilization stress were significantly decreased compared with the control group. Dual-labeling immunofluorescence revealed that the expression of leptin receptor and the co-localization coeffient in these leptic receptor neurons in the arcuate nucleus of the hypothalamus were both upregulated, while the number of neuropeptide Y neurons was decreased. Chronic immobilization stress induced high expression of leptin receptor in the arcuate nucleus and suppressed the synthesis and secretion of neuropeptide Y, thereby disrupting the pathways in the arcuate nucleus that regulate feeding behavior, resulting in diminished food intake and reduced body weight. 展开更多
关键词 neural regeneration chronic immobilization stress HYPOTHALAMUS arcuate nucleus doubleimmunofluorescence neuropeptide Y leptin receptor feeding center body weight grants-supported paper NEUROREGENERATION
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Hydration Characteristics and Immobilization of Cr(Ⅵ) in Slag Cement-CKD Pastes under Hydrothermal Treatment 被引量:2
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作者 M R Shatat Gomaa A M Ali M A Tantawy 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2015年第5期1013-1019,共7页
The effect of hydrothermal curing regimes on the hydration characteristics of slag cement containing different ratios of cement kiln dust has been studied. The samples for this study were combination of slag cement an... The effect of hydrothermal curing regimes on the hydration characteristics of slag cement containing different ratios of cement kiln dust has been studied. The samples for this study were combination of slag cement and cement kiln dust(5%-25%) without and with immobilization of 5% Cr(VI) by mass. Pastes were hydrothermally treated at 180 ℃ for different periods(2-24 h) in well closed stainless steel capsule. The hydration characteristics of these pastes were studied by measuring the compressive strength, bulk density, total porosity and combined water content. The findings were further supported by XRD and SEM analysis. The results indicated that the hydration characteristics of slag cement paste containing cement kiln dust 10% by mass were enhanced, especially at later ages(24 h) of hydration. That is due to the hydrothermal curing regimes of immobilized pastes accelerating hydration reactions and precipitation of Ca Cr O4, indicating that Cr(VI) can be solidified in the cement paste. This precipitation leads to pore formation in hydrated slag cement pastes. 展开更多
关键词 HYDROTHERMAL immobilization slag cement CKD pastes
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Photochemical surface modification of poly(arylsulfone) ultrafiltration membrane and covalent immobilization of enzyme 被引量:2
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作者 SONGHua WUGuang-xia LIUKai 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2004年第3期392-396,共5页
The sensitivity of poly(arylsulfone)(PSf) for UV irradiation in different solvents(water and ethanol) was investigated. It is confirmed that acrylic acid(AA) and acrylamide(AAm) are grafted only onto the surface of th... The sensitivity of poly(arylsulfone)(PSf) for UV irradiation in different solvents(water and ethanol) was investigated. It is confirmed that acrylic acid(AA) and acrylamide(AAm) are grafted only onto the surface of the membrane instead of the interior by FTIR and scanning electron microscope(SEM). The membrane performance(Δ J/J 0 and contact angle θ ) after photografting was studied. In the range of conditions used, the grafting yield increases with irradiation time and monomer concentration growing. After photografting and N 3 dimethyl aminopropyl N' ethycarbodiimide hydrochloride(EDC) activation, PSf membrane was immobilized with hydrogen peroxide oxidoreductase, and showed a higher activity than the control membrane. 展开更多
关键词 PHOTOGRAFTING poly(arylsulfone) ultrafiltration membrane immobilization
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