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Studies on Agarofurans Ⅱ.Stereoselective Synthesis of 1α-and 1β-Methyl Agarofuran
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作者 Wu Yan ZHANG Ji Yu GUO Xiao Tian LIANG (Insitute of Materia Medica, Chinese Academy of Med. Sci. & Peking Union Med. College, Beijing 100050) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第6期491-492,共2页
1α- and 1β-methyl agarofuran 1 and 2 were stereoselectively synthesized. the key intermediates being synthesized through stereoselective Robinson annulation.The conjugated double bond was redined in an improved way... 1α- and 1β-methyl agarofuran 1 and 2 were stereoselectively synthesized. the key intermediates being synthesized through stereoselective Robinson annulation.The conjugated double bond was redined in an improved way. Alkylation of imine 7 with enone 8, 9, 10 was performed 展开更多
关键词 and 1 Stereoselective synthesis of 1 Studies on agarofurans Methyl agarofuran
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Studies on Agarofurans Ⅰ. New Synthesis of Nor-Ketoagarofuran and 4-Hydroxydihydroagarofuran
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作者 Wu-Yan ZHANG Ji Yu GUO Xiao Tian LIANG(Institute of Materia Medica, Chinese Academy of Medical Sciences &Peking Union Medical College, Beijing 100050) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第1期25-26,共2页
Nor-ketoagarofuran (1), one of the furanoids isolated from grnd Oil, has been Synthesed in a preprative scale in high yield from olefin 3 in 3 steps. Reaction of norketoagarofuran (1) with CH3MgI afforded 4 (2), an an... Nor-ketoagarofuran (1), one of the furanoids isolated from grnd Oil, has been Synthesed in a preprative scale in high yield from olefin 3 in 3 steps. Reaction of norketoagarofuran (1) with CH3MgI afforded 4 (2), an another naturallyoccurring tetrahydrofuran derivative. 展开更多
关键词 KBR Studies on agarofurans New synthesis of Nor-Ketoagarofuran and 4-Hydroxydihydroagarofuran
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Studies on Agarofurans VIII. Synthesis of the Metabolites of 4-Butyl-a-agarofuran 被引量:3
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作者 Chun Li Wu Yan Zhang +1 位作者 Ji Yu Guo Xiao Tian Liang 《Chinese Chemical Letters》 SCIE CAS CSCD 2002年第1期19-22,共4页
The structures of five metabolites (2-6) of agarofuran 1 were confirmed by synthesis. The configuration of the secondary hydroxyl in 7 was determined by Horeau抯 method. The configuration of C-2 in compound 4 and 5 ... The structures of five metabolites (2-6) of agarofuran 1 were confirmed by synthesis. The configuration of the secondary hydroxyl in 7 was determined by Horeau抯 method. The configuration of C-2 in compound 4 and 5 was determined by their stereochemistry and NMR. 展开更多
关键词 agarofuran METABOLITE synthesis.
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Studies on Agarofurans Ⅳ. The Synthesis of 4-Substitutioned Agarofurans 被引量:2
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作者 Wu Yan ZHANG Ji Yu GUO Xiao Tian LIANG (Institute of Materia Medica. Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100050) 《Chinese Chemical Letters》 SCIE CAS CSCD 2000年第5期399-400,共2页
A new synthetic route for α -agarofuran(1b) is described. Several agarofuran derivatives were synthesized in similar way. Derivative 1d was also synthesized in a novel way, in which the substitution at C-4 was perfor... A new synthetic route for α -agarofuran(1b) is described. Several agarofuran derivatives were synthesized in similar way. Derivative 1d was also synthesized in a novel way, in which the substitution at C-4 was performed quantitatively. An ideal condition for cyclization of diol 7 to agarofuran (1) was found. 展开更多
关键词 agarofuran synthesis.
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New Stereoselective Synthesis of 4-Butyl-α-agarofuran 被引量:1
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作者 Chun LI, Da Li YIN, Hui Qin HUANG, Xiang Hong WU, Ji Yu GUOInstitute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100050 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第9期881-882,共2页
A potent anxiolytic 4-butyl-α-agarofuran (AF-5) was synthesized from (+)dihydro-carvone. Acid catalyzed hydration of (+)dihydrocarvone and interconversion with β-O-ketone 8 and the key intermediate α,β-unsaturated... A potent anxiolytic 4-butyl-α-agarofuran (AF-5) was synthesized from (+)dihydro-carvone. Acid catalyzed hydration of (+)dihydrocarvone and interconversion with β-O-ketone 8 and the key intermediate α,β-unsaturated ketone 5 made this synthesis more practical. 展开更多
关键词 AF-5 stereoselective synthesis.
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Studies on Agarofurans Ⅲ. The Synthesis of 3-Substituted Agarofurans
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作者 Wu Yan ZHANG Ji Yu GUO Xiao Tian LIANG (Institute of Materia Medica. Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100050) 《Chinese Chemical Letters》 SCIE CAS CSCD 2000年第4期301-304,共4页
14-Nor-3-oxodihydroagarofuran (2) was prepared in high yield. From 2, derivatives12 and 13 were synthesized by Grignard addition. In order to identify the configuration of C-3 in compound 12 and 13, the sterospecific ... 14-Nor-3-oxodihydroagarofuran (2) was prepared in high yield. From 2, derivatives12 and 13 were synthesized by Grignard addition. In order to identify the configuration of C-3 in compound 12 and 13, the sterospecific synthesis of compound 12 has been carried out in 5 steps from octalone (14). 展开更多
关键词 agarofuran synthesis
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Efficient electrocatalytic urea synthesis from CO_(2)and nitrate over the scale-up produced FeNi alloy-decorated nanoporous carbon
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作者 Zuo-Shu Sun Xue-Yan Xiang +6 位作者 Qiu-Ping Zhao Zhao Tang Shi-Yi Jiang Tong-Bu Lu Zhi-Ming Zhang Baifan Wang Hua-Qing Yin 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第10期153-162,共10页
Electrocatalytic urea synthesis provides a favorable strategy for conventional energy-consuming urea synthesis,but achieving large-scale catalyst synthesis with high catalytic efficiency remains challenging.Herein,we ... Electrocatalytic urea synthesis provides a favorable strategy for conventional energy-consuming urea synthesis,but achieving large-scale catalyst synthesis with high catalytic efficiency remains challenging.Herein,we developed a simple method for the preparation of a series of FeNi-alloy-based catalysts,named FeNi@nC-T(n represents the content of nanoporous carbon as 1,3,5,7 or 9 g and T=900,950,1000 or 1100°C),for highly performed urea synthesis via NO_(3)−and CO_(2)co-reduction.The FeNi@7C-1000 achieved a high urea yield of 1041.33 mmol h^(−1)gFeNi^(−1)with a Faradaic efficiency of 15.56%at–1.2 V vs.RHE.Moreover,the scale-up synthesized FeNi@7C-950-S(over 140 g per batch)was achieved with its high catalytic performance and high stability maintained.Mechanism investigation illuminated that the Ni and Fe sites catalyze and stabilize the key*CO and*N intermediates and minimize the C–N coupling reaction barriers for highly efficient urea synthesis. 展开更多
关键词 Urea synthesis ELECTROCATALYSIS FeNi alloy Scale-up synthesis C-N coupling
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Insight into microbial synthesis of metal nanomaterials and their environmental applications:Exploration for enhanced controllable synthesis
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作者 Yuqing Liu Yu Yang +3 位作者 Yuhan E Changlong Pang Di Cui Ang Li 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第11期6-15,共10页
Microbial fabrication of metal nanoparticles(MNPs)has received significant attention due to the advantages of low toxicity,energy efficiency and ecological safety.Diverse groups of MNPs can be synthesized intracellula... Microbial fabrication of metal nanoparticles(MNPs)has received significant attention due to the advantages of low toxicity,energy efficiency and ecological safety.Diverse groups of MNPs can be synthesized intracellularly or extracellularly by various wild-type microorganisms,including bacteria,fungi,algae and viruses.Synthetic biology approaches,represented by genetic engineering,have been applied to overcome the shortcomings in productivity,stability,and controllability of biosynthetic MNPs.Scanning electron microscope(SEM),transmission electron microscope(TEM)and other characterization techniques assist in deciphering their unique properties.In addition,biosynthetic MNPs have been widely explored for the utilization in environmental remediation and contaminant detection.And machine learning contains a great potential for designing targeted MNPs and predicting their toxicity.This review provides a comprehensive overview of the research progress in the microbial synthesis of MNPs.An outlook on the current challenges and future prospects in the biologically controllable synthesis and engineering environmental applications of MNPs is also provided in this review. 展开更多
关键词 Microbial synthesis Metal nanoparticles Controllable synthesis Synthetic biology Environmental applications
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Research Progress on Synthesis of Superoxide Dismutase Mimics
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作者 Delong Bao Xiao Han Anhe Jia 《Expert Review of Chinese Chemical》 2024年第2期15-22,共8页
Research on the synthesis of superoxide dismutase mimics by chemical and biologi-cal synthetic methods were reviewed.The advantages and limitations were analyzed.A prospect for the future development of superoxide dis... Research on the synthesis of superoxide dismutase mimics by chemical and biologi-cal synthetic methods were reviewed.The advantages and limitations were analyzed.A prospect for the future development of superoxide dismutase mimics is proposed. 展开更多
关键词 superoxide dismutase chemical synthesis biological synthesis REVIEW
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Templated synthesis of transition metal phosphide electrocatalysts for oxygen and hydrogen evolution reactions 被引量:4
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作者 Rose Anne Acedera Alicia Theresse Dumlao +4 位作者 DJ Donn Matienzo Maricor Divinagracia Julie Anne del Rosario Paraggua Po-Ya Abel Chuang Joey Ocon 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第2期646-669,I0014,共25页
Transition metal phosphides(TMPs)have been regarded as alternative hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)catalysts owing to their comparable activity to those of noble metal-based catalysts... Transition metal phosphides(TMPs)have been regarded as alternative hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)catalysts owing to their comparable activity to those of noble metal-based catalysts.TMPs have been produced in various morphologies,including hollow and porous nanostructures,which are features deemed desirable for electrocatalytic materials.Templated synthesis routes are often responsible for such morphologies.This paper reviews the latest advances and existing challenges in the synthesis of TMP-based OER and HER catalysts through templated methods.A comprehensive review of the structure-property-performance of TMP-based HER and OER catalysts prepared using different templates is presented.The discussion proceeds according to application,first by HER and further divided among the types of templates used-from hard templates,sacrificial templates,and soft templates to the emerging dynamic hydrogen bubble template.OER catalysts are then reviewed and grouped according to their morphology.Finally,prospective research directions for the synthesis of hollow and porous TMP-based catalysts,such as improvements on both activity and stability of TMPs,design of environmentally benign templates and processes,and analysis of the reaction mechanism through advanced material characterization techniques and theoretical calculations,are suggested. 展开更多
关键词 OER HER Transition metal phosphide Templated synthesis ELECTROCATALYSTS
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Facile synthesis of hierarchical NaX zeolite from natural kaolinite for efficient Knoevenagel condensation 被引量:2
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作者 Wen Xiao Peng Dong +6 位作者 Chan Wang Jingdong Xu Tiesen Li Haibo Zhu Tinghai Wang Renwei Xu Yuanyuan Yue 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第1期75-84,共10页
Zeolite catalysts have found extensive applications in the synthesis of various fine chemicals.However,the micropores of zeolites impose diffusion limitations on bulky molecules,greatly reducing the catalytic efficien... Zeolite catalysts have found extensive applications in the synthesis of various fine chemicals.However,the micropores of zeolites impose diffusion limitations on bulky molecules,greatly reducing the catalytic efficiency.Herein,we explore an economic and environmentally friendly method for synthesizing hierarchical NaX zeolite that exhibits improved catalytic performance in the Knoevenagel condensation reaction for producing the useful fine chemical 2-cyano-3-phenylacrylate.The synthesis was achieved via a low-temperature activation of kaolinite and subsequent in-situ transformation strategy without any template or seed.Systematic characterizations reveal that the synthesized NaX zeolite has both intercrystalline and intra-crystalline mesopores,smaller crystal size,and larger external specific surface area compared to commercial NaX zeolite.Detailed mechanism investigations show that the inter-crystalline mesopores are generated by stacking smaller crystals formed from in-situ crystallization of the depolymerized kaolinite,and the intra-crystalline mesopores are inherited from the pores in the depolymerized kaolinite.This synthesis strategy provides an energy-saving and effective way to construct hierarchical zeolites,which may gain wide applications in fine chemical manufacturing. 展开更多
关键词 Hierarchical NaX zeolite Template-free synthesis Natural kaolinite Knoevenagel condensation
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Optimal synthesis of heat-integrated distillation configurations using the two-column superstructure 被引量:1
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作者 Xiaodong Zhang Lu Jin Jinsheng Sun 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第2期238-249,共12页
In the realm of the synthesis of heat-integrated distillation configurations,the conventional approach for exploring more heat integration possibilities typically entails the splitting of a single column into a twocol... In the realm of the synthesis of heat-integrated distillation configurations,the conventional approach for exploring more heat integration possibilities typically entails the splitting of a single column into a twocolumn configuration.However,this approach frequently necessitates tedious enumeration procedures,resulting in a considerable computational burden.To surmount this formidable challenge,the present study introduces an innovative remedy:The proposition of a superstructure that encompasses both single-column and multiple two-column configurations.Additionally,a simultaneous optimization algorithm is applied to optimize both the process parameters and heat integration structures of the twocolumn configurations.The effectiveness of this approach is demonstrated through a case study focusing on industrial organosilicon separation.The results underscore that the superstructure methodology not only substantially mitigates computational time compared to exhaustive enumeration but also furnishes solutions that exhibit comparable performance. 展开更多
关键词 SUPERSTRUCTURE Process synthesis Heat integration Simulation-based optimization Industrial organosilicon separation
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Microfluidic-oriented synthesis of enriched iridium nanodots/carbon architecture for robust electrocatalytic nitrogen fixation 被引量:1
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作者 Hengyuan Liu Xingjiang Wu +2 位作者 Yuhao Geng Xin Li Jianhong Xu 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第3期544-555,共12页
Electrocatalytic nitrogen reduction reaction(NRR)is considered as a promising candidate to achieve ammonia synthesis because of clean electric energy,moderate reaction condition,safe operating process and harmless by-... Electrocatalytic nitrogen reduction reaction(NRR)is considered as a promising candidate to achieve ammonia synthesis because of clean electric energy,moderate reaction condition,safe operating process and harmless by-products.However,the chemical inertness of nitrogen and poor activated capacity on catalyst surface usually produce low ammonia yield and faradic efficiency.Herein,the microfluidic technology is proposed to efficiently fabricate enriched iridium nanodots/carbon architecture.Owing to in-situ co-precipitation reaction and microfluidic manipulation,the iridium nanodots/carbon nanomaterials possess small average size,uniform dispersion,high conductivity and abundant active sites,producing good proton activation and rapid electrons transmission and moderate adsorption/desorption capacity.As a result,the as-prepared iridium nanodots/carbon nanomaterials realize large ammonia yield of 28.73 μg h^(-1) cm^(-2) and faradic efficiency of 9.14%in KOH solution.Moreover,the high ammonia yield of 11.21 μg h^(-1) cm^(-2) and faradic efficiency of 24.30%are also achieved in H_(2)SO_(4) solution.The microfluidic method provides a reference for large-scale fabrication of nano-sized catalyst materials,which may accelerate the progress of electrocatalytic NRR in industrialization field. 展开更多
关键词 Iridium nanodots CARBON Microfluidic technology Efficient synthesis Electrocatalytic nitrogen fixation
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Boosting Fischer-Tropsch Synthesis via Tuning of N Dopants in TiO_(2)@CN-Supported Ru Catalysts 被引量:1
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作者 Xincheng Li Yunhao Liu +10 位作者 Dejian Zhao Shuaishuai Lyu Jingwei Ye Xiaoshen Li Peipei Wu Ye Tian Yingtian Zhang Tong Ding Song Song Qingpeng Cheng Xingang Li 《Transactions of Tianjin University》 EI CAS 2024年第1期90-102,共13页
Nitrogen(N)-doped carbon materials as metal catalyst supports have attracted signifi cant attention,but the eff ect of N dopants on catalytic performance remains unclear,especially for complex reaction processes such ... Nitrogen(N)-doped carbon materials as metal catalyst supports have attracted signifi cant attention,but the eff ect of N dopants on catalytic performance remains unclear,especially for complex reaction processes such as Fischer-Tropsch synthesis(FTS).Herein,we engineered ruthenium(Ru)FTS catalysts supported on N-doped carbon overlayers on TiO_(2)nanoparticles.By regulating the carbonization temperatures,we successfully controlled the types and contents of N dopants to identify their impacts on metal-support interactions(MSI).Our fi ndings revealed that N dopants establish a favorable surface environment for electron transfer from the support to the Ru species.Moreover,pyridinic N demonstrates the highest electron-donating ability,followed by pyrrolic N and graphitic N.In addition to realizing excellent catalytic stability,strengthening the interaction between Ru sites and N dopants increases the Ru^(0)/Ru^(δ+)ratios to enlarge the active site numbers and surface electron density of Ru species to enhance the strength of adsorbed CO.Consequently,it improves the catalyst’s overall performance,encompassing intrinsic and apparent activities,as well as its ability for carbon chain growth.Accordingly,the as-synthesized Ru/TiO_(2)@CN-700 catalyst with abundant pyridine N dopants exhibits a superhigh C_(5+)time yield of 219.4 mol CO/(mol Ru·h)and C_(5+)selectivity of 85.5%. 展开更多
关键词 Fischer-Tropsch synthesis N-doped carbon materials Ruthenium catalyst Pyridinic N Metal-N interaction
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Room Temperature Synthesis of Vertically Aligned Amorphous Ultrathin NiCo-LDH Nanosheets Bifunctional Flexible Supercapacitor Electrodes 被引量:1
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作者 Kwadwo Asare Owusu Zhaoyang Wang +7 位作者 Ali Saad Felix Ofori Boakye Muhammad Asim Mushtaq Muhammad Tahir Ghulam Yasin Dongqing Liu Zhengchun Peng Xingke Cai 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第2期277-286,共10页
Developing a simple scalable method to fabricate electrodes with high capacity and wide voltage range is desired for the real use of electrochemical supercapacitors.Herein,we synthesized amorphous NiCo-LDH nanosheets ... Developing a simple scalable method to fabricate electrodes with high capacity and wide voltage range is desired for the real use of electrochemical supercapacitors.Herein,we synthesized amorphous NiCo-LDH nanosheets vertically aligned on activated carbon cloth substrate,which was in situ transformed from Co-metal-organic framework materials nano-columns by a simple ion exchange process at room temperature.Due to the amorphous and vertically aligned ultrathin structure of NiCo-LDH,the NiCo-LDH/activated carbon cloth composites present high areal capacities of 3770 and 1480 mF cm^(-2)as cathode and anode at 2 mA cm^(-2),and 79.5%and 80%capacity have been preserved at 50 mA cm^(-2).In the meantime,they all showed excellent cycling performance with negligible change after>10000 cycles.By fabricating them into an asymmetric supercapacitor,the device achieves high energy densities(5.61 mWh cm^(-2)and 0.352 mW cm^(-3)).This work provides an innovative strategy for simplifying the design of supercapacitors as well as providing a new understanding of improving the rate capabilities/cycling stability of NiCo-LDH materials. 展开更多
关键词 amorphous nanosheets aqueous supercapacitor high volumetric/areal energy density NiCo-LDH room temperature synthesis
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Cost-Effective Method of Gene Synthesis by Sequencing from Microchip-Derived Oligos for Droplet Cloning
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作者 Kimberly Wang 《Advances in Bioscience and Biotechnology》 CAS 2024年第8期474-485,共12页
Gene synthesis has provided important contributions in various fields including genomics and medicine. Current genes are 7 - 30 cents depending on the assembly and sequencing methods performed. Demand for gene synthes... Gene synthesis has provided important contributions in various fields including genomics and medicine. Current genes are 7 - 30 cents depending on the assembly and sequencing methods performed. Demand for gene synthesis has been increasing for the past few decades, yet available methods remain expensive. A solution to this problem involves microchip-derived oligonucleotides (oligos), an oligo pool with a substantial number of oligo fragments. Microchips have been proposed as a tool for gene synthesis, but this approach has been criticized for its high error rate during sequencing. This study tests a possible cost-effective method for gene synthesis utilizing fragment assembly and golden gate assembly, which can be employed for quicker manufacturing and efficient execution of genes in the near future. The droplet method was tested in two trials to determine the viability of the method through the accuracy of the oligos sequenced. A preliminary research experiment was performed to determine the efficacy of oligo lengths ranging from two to four overlapping oligos through Gibson assembly. Of the three oligo lengths tested, only two fragment oligos were correctly sequenced. Two fragment oligos were used for the second experiment, which determined the efficacy of the droplet method in reducing gene synthesis cost and speed. The first trial utilized a high-fidelity polymerase and resulted in 3% correctly sequenced oligos, so the second trial utilized a non-high-fidelity polymerase, resulting in 8% correctly sequenced oligos. After calculating, the cost of gene synthesis lowers down to 0.8 cents/base. The final calculated cost of 0.8 cents/base is significantly cheaper than other manufacturing costs of 7 - 30 cents/base. Reducing the cost of gene synthesis provides new insight into the cost-effectiveness of present technologies and protocols and has the potential to benefit the fields of bioengineering and gene therapy. 展开更多
关键词 COST-EFFECTIVE Gene synthesis MICROCHIP Oligo Droplet Cloning
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Rapid Green Synthesis of Silver Nanoparticles by Reishi and Their Antibacterial Activity and Mechanisms
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作者 Akamu J. Ewunkem T’nasia Priester +4 位作者 Desia Williams Bailey Ariyon Ilunga Tshimanga Brittany Justice Dinesh K. Singh 《Journal of Biomaterials and Nanobiotechnology》 2024年第3期51-63,共13页
Nanotechnology is a rapidly growing field in biomedical engineering with references to efficiency, safety, and cost-effective approaches. Herein, the objective of this study was to examine an innovative approach to ra... Nanotechnology is a rapidly growing field in biomedical engineering with references to efficiency, safety, and cost-effective approaches. Herein, the objective of this study was to examine an innovative approach to rapidly synthesis silver nanoparticles from an aqueous extract of medicinal mushroom Ganoderma lucidum (also known as reishi). The structural and dimensional dispersion of the biosynthesized silver nanoparticles from reishi was confirmed by UV-Vis spectrophotometer (UV-Vis) and Scanning Electron Microscopy (SEM) analysis. Additionally, the biosynthesized silver nanoparticles from resihi were used to explore their potential antimicrobial activity against Staphylococcus aureus and Micrococcus luteus and Escherichia coli and Klebsiella pneumoniae. The results from this study revealed that the silver nanoparticles mediated by reishi adopted a spherical shape morphology with sizes, less than 100 nm and revealed strong absorption plasmon band at 440 nm. Furthermore, the biosynthesized silver nanoparticles from reishi exhibited antibacterial activity against the tested S. aureus and M. luteus and E. coli and K. pneumoniae by altering their morphology which signifies their biomedical potential. 展开更多
关键词 NANOTECHNOLOGY REISHI Nanoparticles ANTIMICROBIAL Green synthesis
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Green Synthesis of Silver Nanoparticles Using Aqueous Orange and Lemon Peel Extract and Evaluation of Their Antimicrobial Properties
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作者 Amra Bratovcic Amna Dautovic 《Advances in Nanoparticles》 CAS 2024年第2期11-28,共18页
Green synthesis of silver nanoparticles (AgNPs) using aqueous extracts of orange and lemon peels, as a reducing agent, and silver nitrate salts as a source of silver ions is a promising field of research due to the ve... Green synthesis of silver nanoparticles (AgNPs) using aqueous extracts of orange and lemon peels, as a reducing agent, and silver nitrate salts as a source of silver ions is a promising field of research due to the versatility of biomedical applications of metal nanoparticles. In this paper, AgNPs were synthetized at different reaction parameters such as the type and concentration of the extracts, metal salt concentration, temperature, speed stirring, and pH. The antibacterial properties of the obtained silver nanoparticles against E. coli, as well as the physical and chemical characteristics of the synthesized silver nanoparticles, were investigated. UV-Vis spectroscopy was used to confirm the formation of AgNPs. In addition to green biogenic synthesis, chemical synthesis of silver nanoparticles was also carried out. The optimal temperature for extraction was 65˚C, while for the synthesis of AgNPs was 35˚C. The synthesis is carried out in an acidic environment (pH = 4.7 orange and pH = 3.8 lemon), neutral (pH = 7) and alkaline (pH = 10), then for different concentrations of silver nitrate solution (0.5 mM - 1 mM), optimal time duration of the reaction was 60 min and optimal stirring speed rotation was 250 rpm on the magnetic stirrer. The physical properties of the synthesized silver nanoparticles (conductivity, density and refractive index) were also studied, and the passage of laser light through the obtained solution and distilled water was compared. Positive inhibitory effect on the growth of new Escherichia coli colonies have shown AgNPs synthesized at a basic pH value and at a 0.1 mM AgNO<sub>3</sub> using orange or lemon peel extract, while for a 0.5 mM AgNO<sub>3 </sub>using lemon peel extract. 展开更多
关键词 Green synthesis Silver Nanoparticles Orange and Lemon Peel Extract Antibacterial Activity Escherichia coli
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Process synthesis for the separation of coal-to-ethanol products
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作者 Qingping Qu Daoyan Liu +1 位作者 Hao Lyu Jinsheng Sun 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第5期263-278,共16页
The coal-to-ethanol process,as the clean coal utilization,faces challenges from the energy-intensive distillation that separates multi-component effluents for pure ethanol.Referring to at least eight columns,the synth... The coal-to-ethanol process,as the clean coal utilization,faces challenges from the energy-intensive distillation that separates multi-component effluents for pure ethanol.Referring to at least eight columns,the synthesis of the ethanol distillation system is impracticable for exhaustive comparison and difficult for conventional superstructure-based optimization as rigorous models are used.This work adopts a superstructure-based framework,which combines the strategy that adaptively selects branches of the state-equipment network and the parallel stochastic algorithm for process synthesis.High-performance computing significantly reduces time consumption,and the adaptive strategy substantially lowers the complexity of the superstructure model.Moreover,parallel computing,elite search,population redistribution,and retention strategies for irrelevant parameters are used to improve the optimization efficiency further.The optimization terminates after 3000 generations,providing a flowsheet solution that applies two non-sharp splitting options in its distillation sequence.As a result,the 59-dimension superstructure-based optimization was solved efficiently via a differential evolution algorithm,and a high-quality solution with a 28.34%lower total annual cost than the benchmark was obtained.Meanwhile,the solution of the superstructure-based optimization is comparable to that obtained by optimizing a single specific configuration one by one.It indicates that the superstructure-based optimization that combines the adaptive strategy can be a promising approach to handling the process synthesis of large-scale and complex chemical processes. 展开更多
关键词 Coal-to-ethanol Process synthesis Superstructure-based optimization Differential evolution algorithm DISTILLATION
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Ultrafast synthesis of nanocrystalline spinel oxides by Joule-heating method
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作者 Wenxuan Yang Long Shang +4 位作者 Xiaomeng Liu Sihan Zhang Haixia Li Zhenhua Yan Jun Chen 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第11期517-521,共5页
Spinel oxides,with the formula AB_(2)O_(4)(A and B represent metal ions)perform superior electrocatalytic characteristic when A and B are transition metals like Co,Fe,Mn,etc.Abundant researches have been attached to t... Spinel oxides,with the formula AB_(2)O_(4)(A and B represent metal ions)perform superior electrocatalytic characteristic when A and B are transition metals like Co,Fe,Mn,etc.Abundant researches have been attached to the structure designments while methods are often energy-intensive and inefficient.Here,we devised a universal strategy to achieve rapid synthesis of nanocrystalline spinel materials with multiple components(Co_(3)O_(4),Mn_(3)O_(4),CoMn_(2)O_(4)and CoFe_(2)O_(4)are as examples),where phase formation is within 15 s.Under the Joule-heating shock,a crack-break process of microcosmic phase transformation is observed by in-situ transmission electron microscopy.The half-wave potential values of Co_(3)O_(4)-JH,Mn_(3)O_(4)-JH,CoMn_(2)O_(4)-JH and CoFe_(2)O_(4)-JH in the electrocatalytic oxygen reduction reaction were 0.77,0.78,0.79 and 0.76,respectively.This suggests that the Joule heating is a fast and efficient method for the preparation of spinel oxide electrocatalysts. 展开更多
关键词 Ultrafast synthesis Spinel oxides Joule-heating In-situ TEM Oxygen reduction
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