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Green Chemistry Allometry Test of Microwave-Assisted Synthesis of Transition Metal Nanostructures
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作者 Victor J. Law Denis P. Dowling 《American Journal of Analytical Chemistry》 CAS 2023年第11期493-518,共26页
Microwave irradiation is considered an important approach to Green Chemistry, because of its ability to rapidly increase the internal temperature of polar-organic compounds that lead to synthesis times of minutes rath... Microwave irradiation is considered an important approach to Green Chemistry, because of its ability to rapidly increase the internal temperature of polar-organic compounds that lead to synthesis times of minutes rather than hours when compared to conventional thermal heating. This works describes a dual allometry test for the discrimination between the solvents and reagents used in the microwave-assisted synthesis of transition metal (zinc oxide, palladium silver, platinum, and gold) nanostructures. The test is performed in log-log process energy phase-space projection, where the synthesis data (kJ against kJ·mol<sup>-1</sup>) has a power-law signature. The test is shown to discriminate between recommended Green Chemistry, problematic Green Chemistry, and Green Chemistry hazardous solvents. Typically, recommended Green chemistry exhibits a broad y-axes distribution within an upper exponent = 1 and lower exponent = 0.5. Problematic Green Chemistry exhibits a y-axes narrower distribution with an upper exponent = 0.94 and lower exponent = 0.64. Non-Green Chemistry hazardous data exhibits a further narrowing of the y-axes distribution within upper exponent = 0.87 and lower exponent = 0.66. In all three cases, the y-axes is aligned to original database power-law signature. It is also shown that in the x-axes direction (process energy budget) the grouped order of magnitude decreases from four orders for recommended Green Chemistry solvent and reagent data, through two orders for non-Green Chemistry hazardous material and down to one order for problematic Green Chemistry. 展开更多
关键词 Microwave-Assisted Synthesis Transition Metals Nanostructures Allometry Scaling Power-Law Signature green chemistry
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A green cross-linking method for the preparation of renewable threedimensional graphene sponges for efficient adsorption of Congo red dye
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作者 Zhuang Liu Bo Gao +3 位作者 Haoyuan Han Yuling Li Haiyang Fu Donghui Wei 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第2期84-93,共10页
Graphene-based materials possess significant potential for the treatment of dye wastewater due to their exceptional adsorption properties toward stubborn pollutants.However,their utilization is hindered by high prepar... Graphene-based materials possess significant potential for the treatment of dye wastewater due to their exceptional adsorption properties toward stubborn pollutants.However,their utilization is hindered by high preparation costs,low yields,environmental pollution during synthesis,and challenges in regenerating the adsorbent.This study proposes a novel approach to address these limitations by developing nitrogen-doped three-dimensional(3D)polyvinyl alcohol(PVA)crosslinked graphene sponges(N-PGA)using a cross-linking method with ammonium carbonate.This method offers a relatively mild,environmentally friendly approach.Ammonium carbonate serves as both a reducing and modifying agent,facilitating the formation of the intrinsic structure of N-PGA and acting as a nitrogen source.Meanwhile,PVA is utilized as the cross-linking agent.The results demonstrate that N-PGA exhibits a favorable internal 3D hierarchical porous structure and possesses robust mechanical properties.The measured specific surface area(BET)of N-PGA was as high as406.538 m^(2)·g^(-1),which was favorable for its efficient adsorption of Congo red(CR)dye molecules.At an initial concentration of 50 mg·L^(-1),N-PGA achieved an impressive removal rate of 89.6%and an adsorption capacity of 112 mg·g^(-1)for CR dye.Furthermore,it retained 79%of its initial adsorption capacity after 10 cycles,demonstrating excellent regeneration performance.In summary,the synthesized N-PGA displays remarkable efficacy in the adsorption of CR dye in wastewater,opening up new possibilities for utilizing 3D porous graphene nanomaterials as efficient adsorbents in wastewater treatment. 展开更多
关键词 green chemistry Graphene sponge Adsorbents ADSORPTION Congo red Regeneration
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Promotion of GSC Technology Innovation by the Green and Sustainable Chemistry Network 被引量:1
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作者 Kazuhiko Hiyoshi Takashi Ushikubo 《Journal of Chemistry and Chemical Engineering》 2010年第5期14-16,共3页
The Green and Sustainable Chemistry Network (GSCN) has been promoting GSC technology development since 2000 in three major activities, holding the GSC symposium, running the GSC Awards, and providing the information... The Green and Sustainable Chemistry Network (GSCN) has been promoting GSC technology development since 2000 in three major activities, holding the GSC symposium, running the GSC Awards, and providing the information related to GSC in Japan. GSCN holds a vision to expand the philosophy of GSC not only to the domestic, but also to the global. As for a regional network in Asia and Oceania, we established the Asia-Oceania GSC Network, and we hope to expand the Network to all countries. 展开更多
关键词 green and Sustainable chemistry green chemistry Sustainable chemistry Asia-Oceania Network.
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Gold-catalyzed addition reaction between creatinine and isatin:A sustainable and green chemistry approach for the diastereoselective synthesis of 3-substituted-3-hydroxyisatins
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作者 K. Parthasarathy T. Ponpandian C. Praveen 《Chinese Journal of Catalysis》 CSCD 北大核心 2017年第5期775-783,共9页
The aldolization of various isatins with creatinine under gold catalysis in water has been developed.The reaction is operationally simple as the products can be isolated by simple filtration without requiring tedious ... The aldolization of various isatins with creatinine under gold catalysis in water has been developed.The reaction is operationally simple as the products can be isolated by simple filtration without requiring tedious solvent extraction and column chromatographic techniques.The generality of this methodology is showcased through the reactions of a wide range of isatin derivatives with creatinine to afford the respective aldol products in excellent yields with complete syn‐selectivity.The scope of this chemistry is further extended to a tandem reaction involving isatins,creatinine and malononitrile to afford multicomponent products in excellent yields with complete anti‐selectivity.The antioxidant potency of the synthesized compound was assessed by a spectrophotometric method,which revealed that three compounds containing halogen atoms(2c,2d and2e)were the most active compared with the standard. 展开更多
关键词 CREATININE Gold catalysis green chemistry DIASTEREOSELECTIVITY ANTIOXIDANT
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Microwave Assisted One-Pot Preparation of Quinoline Derivatives without any Solvent According to Green Chemistry
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作者 Behrooz Mirza Sepehr Sadegh Samiei 《Journal of Chemistry and Chemical Engineering》 2011年第7期644-647,共4页
The convenient and efficient procedure for one-pot preparation of quinaldine derivatives from multi component reaction of anilines, acetone and benzaldehyde without any solvent under microwave irradiation on the surfa... The convenient and efficient procedure for one-pot preparation of quinaldine derivatives from multi component reaction of anilines, acetone and benzaldehyde without any solvent under microwave irradiation on the surface of alumina impregnated with hydrochloric acid is developed. 展开更多
关键词 MCRS quinoline derivatives ONE-POT microwave SOLVENT-FREE green chemistry.
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The Technology of Green Chemistry and Its Function in Redox Response and: Environmentally Friendly Technology for Sustainable Development: Assessment of Recent Findings
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作者 Meselu Eskezia Ayalew Thevabakthi Siluvai Muthu Arul Jeevan 《Advances in Chemical Engineering and Science》 CAS 2022年第3期131-144,共14页
Sustainability is the ability to nurture or support a process for a long time without compromising the needs of future generations. Rather, sustainable chemistry is a term that refers to the production of chemical pro... Sustainability is the ability to nurture or support a process for a long time without compromising the needs of future generations. Rather, sustainable chemistry is a term that refers to the production of chemical products and processes that reduce or eliminate the use and production of hazardous substances. Green chemistry creates alternative technologies that are safer for human health and the environment to prevent further damage to human health and the environment, such as reducing the release of hazardous chemicals into the air, leading to reduced lung damage. Although sustainable and environmentally friendly technologies have evolved in other areas of science, their use in redox reactions and industry is still in its early stages. The current review aims to highlight the need for green chemistry as a sustainable chemistry and its principles and its application to produce environmentally friendly industrial products and to reduce or stop the production of harmful intermediates and products during its synthesis process. 展开更多
关键词 Atom Economy green chemistry green Technology OXIDATION Reduction
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Developing From Tranditional Microscale Chemistry to Microscale Green Chemistry
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作者 Wing-Hong Chan Albert W. M. Lee 《内蒙古民族大学学报》 2009年第4期9-10,共2页
  Microscale chemistry is appealing to all levels of education.In contrast to conventional macroscale chemistry,only minute amount of chemicals are required to undertaking a chemical investigation.……
关键词 In Developing From Tranditional Microscale chemistry to Microscale green chemistry
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Plasma methods for preparing green catalysts: Current status and perspective 被引量:8
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作者 刘昌俊 李敏悦 +4 位作者 王嘉琪 周昕瞳 郭秋婷 严金茂 李英芝 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第3期340-348,共9页
Most current catalyst preparation methods cause pollution to air, water and land with the use of hazardous chemicals, lengthy operation time, high energy input and excessive water usage. The development of green catal... Most current catalyst preparation methods cause pollution to air, water and land with the use of hazardous chemicals, lengthy operation time, high energy input and excessive water usage. The development of green catalyst preparation is necessary to prevent and eliminate waste from each step of the catalyst preparation. We summarize recent progress in the application of cold plasmas for green catalyst preparation. Cold plasma preparation can reduce the catalyst size, improve the dispersion and enhance catalyst-support interaction with the use of less or no hazardous chemicals. These improvements also lead to the enhancement of catalyst activity and stability. An alternative room temperature electron reduction with a non-hydrogen plasma as an electron source was developed for the reduction of noble metal ions in which no hazardous chemical reducing agent or hydrogen was needed. This creates many opportunities for the development of supported catalysts with heat sensitive substrates, including metal organic frameworks (MOFs), covalent organic framework(COFs), high surface area carbon, peptide, DNA, proteins and others. A novel floating metal catalyst on a water(or solution) surface has been established. Template removal using low temperature cold plasmas also leads to the formation of high surface area porous materials with characteristics that are normally only obtainable with high temperature calcination, but sintering can be avoided. Micro combustion has been developed for the removal of carbon template using cold plasma. This is promising for preparing many structured oxides in a simple way with no use of auxiliary chemicals. Many opportunities exist for the use of cold plasmas to make multi-metallic oxides. Some future development ideas are addressed. 展开更多
关键词 Catalyst preparation PLASMA green chemistry Porous material
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Thermal degradation and hydrolysis depolymerization of printing ink components for plastic packaging in recycling processes: a review
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作者 Jinyang Guo Cong Luo +2 位作者 Zhi Kai Chong Ayah Alassali Kerstin Kuchta 《Frontiers of Environmental Science & Engineering》 SCIE EI CSCD 2024年第10期139-153,共15页
This review covers the decomposition mechanisms of various printing ink binder resins,with a particular focus on their behavior under extrusion conditions in the mechanical recycling process of polyolefin(PO)based pla... This review covers the decomposition mechanisms of various printing ink binder resins,with a particular focus on their behavior under extrusion conditions in the mechanical recycling process of polyolefin(PO)based plastic packaging.Thermal degradation and hydrolysis of the nitrocellulose(NC)-the most used binder for flexographic surface printing on single-layer flexible plastic packaging,occur concurrently during the mechanical recycling process under 160-210℃.For other printing ink binders,polyurethane(PU)noticeable degradation takes place between 200 and 300℃,mostly above 250℃.However,with the involvement of humidity,degradation by hydrolysis can start from 150℃.A similar effect is also discovered with the cellulose acetate(CA)derivatives,which are thermally stable until 300℃ and can be hydrolyzed at 100℃.The thermal stability of polyvinyl butyral(PVB)is not influenced by humidity,with thermal stability ranging from 170 to 260℃,depending on different types.Ultraviolet(UV)-cured acrylics are thermaliy stable until 400℃.The hydrolysis degradation can take place at room temperature.Moreover,this review covers the thermal stability of different colorants used for printing ink application and elaborates on several thermal-stable alternatives of some common colors.This study further reviews how the binder resin affects the quality of recyclates,revealing it to be not only induced by the degradation of the binder resin but also by the immiscibility between the plastic and binder resin.In advanced recycling processes,mainly selective dissolution-precipitation and pyrolysis,the presence of binder resin and its degradation products could stll affect the quality of the product.This review accentuates the imperative need for in-depth research to unravel the impact of printing ink constituents on the quality of recycled products. 展开更多
关键词 Plastic recycling Flexible packaging Polymer degradation green chemistry
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Mass-Based Environmental Factor and Energy Assessment of Microwave-Assisted Synthesized Transition Metal Nanostructures
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作者 Victor J. Law 《American Journal of Analytical Chemistry》 CAS 2024年第6期201-218,共18页
This paper describes mass-based energy phase-space projection of microwave-assisted synthesis of transition metals (zinc oxide, palladium, silver, platinum, and gold) nanostructures. The projection uses process energy... This paper describes mass-based energy phase-space projection of microwave-assisted synthesis of transition metals (zinc oxide, palladium, silver, platinum, and gold) nanostructures. The projection uses process energy budget (measured in kJ) on the horizontal axes and process density (measured in kJg−1) on the vertical axes. These two axes allow both mass usage efficiency (Environmental-Factor) and energy efficiency to be evaluated for a range of microwave applicator and metal synthesis. The metrics are allied to the: second, sixth and eleventh principle of the twelve principle of Green Chemistry. This analytical approach to microwave synthesis (widely considered as a useful Green Chemistry energy source) allows a quantified dynamic environmental quotient to be given to renewable plant-based biomass associated with the reduction of the metal precursors. Thus allowing a degree of quantification of claimed “eco-friendly” and “sustainable” synthesis with regard to waste production and energy usage. 展开更多
关键词 Microwave-Assisted Synthesis Transition Metals Nanostructures Allometry Scaling Power-Law Signature green chemistry
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Green Production Technology of the Monomer of Nylon-6: Caprolactam 被引量:12
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作者 Baoning Zong Bin Sun +5 位作者 Shibiao Cheng Xuhong Mu Keyong Yang Junqi Zhao Xiaoxin Zhang Wei Wu 《Engineering》 SCIE EI 2017年第3期379-384,共6页
After two decades' endeavor, the Research Institute of Petroleum Processing (RIPP) has successfully de- veloped a green caprolactam (CPL) production technology. This technology is based on the integration of tita... After two decades' endeavor, the Research Institute of Petroleum Processing (RIPP) has successfully de- veloped a green caprolactam (CPL) production technology. This technology is based on the integration of titanium silicate (TS)-I zeolite with the slurry-bed reactor for the ammoximation of cyclohexanone, the integration of silicalite-1 zeolite with the moving-bed reactor for the gas-phase rearrangement of cyclohex- anone oxime, and the integration of an amorphous nickel (Ni) catalyst with the magnetically stabilized bed reactor for the purification of caprolactam. The world's first industrial plant based on this green CPL produc- tion technology has been built and possesses a capacity of 200 kt·a-1. Compared with existing technologies, the plant investment is pronouncedly reduced, and the nitrogen (N) atom utilization is drastically improved. The waste emission is reduced significantly; for example, no ammonium sulfate byproduct is produced. As a result, the price difference between CPL and benzene drops. In 2015, the capacity of the green CPL produc- tion technology reached 3 ×10-6 t·a-1, making China the world's largest CPL producer, with a global market share exceeding 50%. 展开更多
关键词 green chemistry green engineering CAPROLACTAM Production technology
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An Efficient and Green Procedure for the Preparation of gem-Dicar- boxylates from Aldehydes Catalyzed by Fe_2(SO_4)_3·xH_2O 被引量:6
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作者 LingJunLI XinYingZHANG GuiShengZHANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2004年第5期508-510,共3页
An efficient and environmentally benign conversion of aldehydes into the corresponding gem-dicarboxylates was realized by using hydrated ferric sulfate as a heterogeneous catalyst. In addition to its high efficiency,... An efficient and environmentally benign conversion of aldehydes into the corresponding gem-dicarboxylates was realized by using hydrated ferric sulfate as a heterogeneous catalyst. In addition to its high efficiency, the catalyst can be recovered simply and reused efficiently for at least seven times. 展开更多
关键词 gem-Dicarboxylates hydrated ferric sulfate protection of aldehydes green chemistry.
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One-Step Preparation of Green Fabric for Continuous Antibacterial Applications 被引量:4
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作者 Rongkang Huang Minghui Hu +10 位作者 Weiwen Liang Juanjuan Zheng Yang Du Yanhuan Lin Huaiming Wang Wentai Guo Zhantao Zeng Chuangkun Li Ming Li Hui Wang Xingcai Zhang 《Engineering》 SCIE EI 2021年第3期326-333,共8页
Polypropylene(PP)scaffolds are the most commonly used biomedical scaffolds despite their disadvan-tages,which include problems with adhesion,infection,and inflammatory responses.Here,we report on the successful develo... Polypropylene(PP)scaffolds are the most commonly used biomedical scaffolds despite their disadvan-tages,which include problems with adhesion,infection,and inflammatory responses.Here,we report on the successful development of a facile one-step method to fabricate a series of novel triclosan poly-dopamine polypropylene(TPP)composite scaffolds and thereby effectively improve the biocompatibility and long-term antibacterial properties of PP scaffolds.The antibacterial triclosan can effectively interact with dopamine during biocompatible polydopamine formation on the PP scaffold by one-step green fab-rication.Thanks to the sustained release of triclosan from the biocompatible polydopamine coating,a 5mm×5mm sample of TPP-coated scaffold made with a triclosan concentration of 8 mg-mL^(-1)(referredto herein as TPP-8)exhibited a continuous antibacterial effect against both Escherichia coli(E.coli)and Staphylococcus aureus(S.aureus)for more than 15d,at maximum antibacterial volumes of 2 and 5mL,respectively.Our study establishes a new direction for facile long-term antibacterial studies for medical applications. 展开更多
关键词 green chemistry Polypropylene scaffold POLYDOPAMINE TRICLOSAN ANTIBACTERIAL
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Nanoscale graphene oxide sheets as highly efficient carbocatalysts in green oxidation of benzylic alcohols and aromatic aldehydes 被引量:2
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作者 Alireza Sedrpoushan Masoud Heidari Omid Akhavan 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2017年第4期745-757,共13页
Nanoscale graphene oxide(NGO)sheets were synthesized and used as carbocatalysts for effectiveoxidation of benzylic alcohols and aromatic aldehydes.For oxidation of alcohols in the presence ofH2O2at80°C,the NGOs(2... Nanoscale graphene oxide(NGO)sheets were synthesized and used as carbocatalysts for effectiveoxidation of benzylic alcohols and aromatic aldehydes.For oxidation of alcohols in the presence ofH2O2at80°C,the NGOs(20%mass fraction)as carbocatalysts showed selectivity toward aldehyde.The rate and yield of this reaction strongly depended on the nature of substituents on the alcohol.For4‐nitrobenzyl alcohol,<10%of it was converted into the corresponding carboxylic acid after24h.By contrast,4‐methoxybenzyl alcohol and diphenylmethanol were completely converted into thecorresponding carboxylic acid and ketone after only9and3h,respectively.The conversion ratesfor oxidation of aromatic aldehydes by NGO carbocatalysts were higher than those for alcohol oxidation.For all the aldehydes,complete conversion to the corresponding carboxylic acids wasachieved using7%(mass fraction)of NGO at70°C within2–3h.Possible mechanisms for NGOcarbocatalyst structure‐dependent oxidation of benzyl alcohols and structure‐independent oxidationof aromatic aldehydes are discussed. 展开更多
关键词 Carbocatalyst Nanoscale graphene oxide green chemistry Oxidation Metal‐free catalyst Colloidal dispersion
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Opportunities and Challenges for the Development of Green Detergents 被引量:1
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作者 Bingbing Shen 《China Detergent & Cosmetics》 2016年第3期10-12,共3页
The characteristic of green detergents and it's difference with regular detergent was expounded in this paper, according to the kernel of green chemistry. The variation trends of Chinese mainstream consumer group sho... The characteristic of green detergents and it's difference with regular detergent was expounded in this paper, according to the kernel of green chemistry. The variation trends of Chinese mainstream consumer group show that the new mainstream consumer group are concerning more and more about household detergent, especially its safety to human and environment. Growing attention of the mainstream consumer group and the standard drafting units on detergent will promote the development of green detergents, however, there are still challenges for the development of green detergents. 展开更多
关键词 green chemistry green detergents CHALLENGES
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Systematic Selection of Green Solvents for Organic Reacting Systems
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作者 Milica Folic Rafiqul Gani +1 位作者 Concepcion Jimenez-Gonzalez David J. C. Constable 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2008年第3期376-383,共8页
The solvent selection methodology developed earlier by. Gani (tal. (Comp. Chem. Eng., 2005)has been extended to handle multi-step reaction systems. The solvent selection problem was formulated based on the methodol... The solvent selection methodology developed earlier by. Gani (tal. (Comp. Chem. Eng., 2005)has been extended to handle multi-step reaction systems. The solvent selection problem was formulated based on the methodology guidelines, and solved using ICAS software tool. A list with solvent candidates is generated so that it can be further investigated experimentally. Comments and clarifications from chemists have been incorporated into the problem forrnulations to clarify the role of the solvents in the chemistry and potential reactivity issues. Highly promising results were obtained, in accordance with. industrial process data. 展开更多
关键词 pharmaceutical synthesis green chemistry green engineering solvent selection computer-aided molecular design
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Multicomponent Reaction in Ionic Liquid: A Novel and Green Synthesis of 1, 4-Dihydropyridine Derivatives
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作者 Xin Ying ZHANG Yan Zhen LI Xue Sen FAN Gui Rong QU Xue Yuan HU Jian Ji WANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第2期150-152,共3页
An efficient and green method for the synthesis of 1, 4-dihydropyridine derivatives mediated in an ionic liquid, [bmim][BF4], through a four-component condensation process of aldehydes, 1, 3-dione, Meldrum's acid and... An efficient and green method for the synthesis of 1, 4-dihydropyridine derivatives mediated in an ionic liquid, [bmim][BF4], through a four-component condensation process of aldehydes, 1, 3-dione, Meldrum's acid and ammonium acetate is disclosed in this paper. 展开更多
关键词 1 4-Dihydropyridines ionic liquids multicomponent reaction green chemistry.
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Green Synthesis of Silver Nanoparticles Using Annona diversifolia Leaf Extract and Their Antimicrobial Application
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作者 Rogelio Solorzano-Toala Daniel Gonzalez-Mendoza +4 位作者 Benjamin Valdez-Salas Vianey Mendez-Trujillo Federico Gutierrez-Miceli Ernesto Beltran-Partida Olivia Tzintzun-Camacho 《Journal of Renewable Materials》 SCIE EI 2020年第9期1129-1137,共9页
The aim of this study was the synthesis of silver nanoparticle using Annona diversifolia Safford.The silver nanoparticles obtained were analyzed by spectroscopic methods and dynamic light scattering methods.The inhibi... The aim of this study was the synthesis of silver nanoparticle using Annona diversifolia Safford.The silver nanoparticles obtained were analyzed by spectroscopic methods and dynamic light scattering methods.The inhibition of AgNPs was evaluated against Bacillus cereus,Klebsiella pneumoniae and Enterobacter aerogenes.The results showed that AgNPs have high values at 3 keV and particle size between 45 to 58 nm with a homogenous morphology.The AgNPs showed growth inhibition against Klebsiella pneumoniae and Enterobacter aerogenes.Therefore studies are needed to confirm the potential antimicrobial of different AgNP from A.diversifolia in Gram negative and Gram positive bacteria. 展开更多
关键词 green chemistry AGNPS PLANTS ANTIMICROBIAL BIOTECHNOLOGY
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Green Method, Optical and Structural Characterization of ZnO Nanoparticles Synthesized Using Leaves Extract of M. oleifera
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作者 Jose Vulfrano Gonzalez-Fernandez Diego David Pinzon-Moreno +1 位作者 Antony Alexander Neciosup-Puican Maria Veronica Carranza-Oropeza 《Journal of Renewable Materials》 SCIE EI 2022年第3期833-847,共15页
ZnO nanoparticles(ZnO-NP)present innovative optical,electrical,and magnetic properties that depend on spe-cific characteristics,e.g.,size,distribution,and morphology.Thus,these properties are essential to address vari... ZnO nanoparticles(ZnO-NP)present innovative optical,electrical,and magnetic properties that depend on spe-cific characteristics,e.g.,size,distribution,and morphology.Thus,these properties are essential to address various applications in areas such as electronics,medicine,energy,and others.In addition,the performance of this ZnO-NP depends of their preparation which can be done by chemical,physical,and biological methods.Meanwhile,nowadays,the main interest in developing ZnO-NP synthesis through biological methods bases on the decrease of use of toxic chemicals or energy applied to the procedures,making the process more cost-effective and environ-mentally friendly.However,the large-scale production of nanoparticles by green synthesis remains a big challenge due to the complexity of the biological extracts used in chemical reactions.That being the case,the preparation of ZnO-NP using Moringa oleifera extract as an alternative biological agent for capping and reduction in synthesis was evaluated in this work.Then,the results based on the analysis of the optical and structural characterization of the ZnO-NP obtained by employing UV-Vis,DLS,zeta potential,XRD,ATR-FTIR,and FE-SEM indicate mostly the presence of spherical nanosized material with a mean hydrodynamic diameter of 47.2 nm measured by DLS and a mean size diameter of 25 nm observed with FE-SEM technique.Furthermore,in FE-SEM images a homo-geneous dispersion and distribution is observed in the absence of agglutination,agglomeration,or generation of significant lumps of the ZnO-NP.The XRD analysis showed that heat annealing induced the crystallite size favor-ing their monocrystallinity.Those obtained data confirm the synthesis of ZnO-NP and the absence of impurities associated with organic compounds in the annealed samples.Finally,those results and low-cost production pre-sent to the synthesized ZnO-NP by this biological method as a useful material in several applications. 展开更多
关键词 ZnO nanoparticles green chemistry Moringa oleifera extract optical characterization structural characterization
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Application and Mechanism of Malonic Acid as a Green Alternative for Protein-Crosslinking
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作者 Donald Szlosek Douglas Currie 《Green and Sustainable Chemistry》 2016年第2期110-115,共6页
Formaldehyde fixation is the main method for crosslinking cellular proteins prior to their usage in immunocytochemistry. In order to create these links, formaldehyde undergoes a Mannich reaction in which the formaldeh... Formaldehyde fixation is the main method for crosslinking cellular proteins prior to their usage in immunocytochemistry. In order to create these links, formaldehyde undergoes a Mannich reaction in which the formaldehyde forms a methylene bridge between the aminogroup of two amino acids. Crosslinking increases protein stability allowing for more accurate preservation of in vivo conformations which in turn increases binding affinity of fluorochrome conjugated antibodies for fluorescent imaging. Formaldehyde is also a known carcinogen as classified by the National Cancer Institute. Malonic acid, a green, plant-based, water-soluble, and relatively inexpensive polycarboxylic acid has been shown to undergo crosslinking of proteins through an unknown mechanism. To test whether malonic acid can crosslink proteins within cells we fixed SH-5YSY cells with either malonic acid or formaldehyde and then stained with a fluorochrome conjugated antibody for the cytoskeletal protein α-tubulin. The cells were then imaged 72 hours after fixation. We observed a non-significant difference in the fluorescence of immunostained SH-5YSY cells fixed with malonic acid as compared to paraformaldehyde (p-value = 0.2469, ANOVA). In addition, we have created a theoretical mechanism showing malonic acid forming a propyl bridge for crosslinking proteins in a similar mechanism to that of formaldehyde. Here, we show that malonic acid is able to fix cells and retain fluorescence just as well as paraformaldehyde up to 72 hours after fixation and present several possible mechanisms for this chemical process. 展开更多
关键词 green chemistry Protein Fixation Protein Crosslinking Cellular Fixation Formaldehyde Fixation FIXATION Malonic Acid
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