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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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The structure-directing role of heterologous seeds in the synthesis of zeolite 被引量:2
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作者 Haoyang Zhang Binyu Wang Wenfu Yan 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第5期792-801,共10页
Zeolites have been widely used as catalysts,ion-exchangers,and adsorbents in chemical industries,detergent industry,steel industry,glass industry,ceramic industry,medical and healthfield,and environmentalfield,and recen... Zeolites have been widely used as catalysts,ion-exchangers,and adsorbents in chemical industries,detergent industry,steel industry,glass industry,ceramic industry,medical and healthfield,and environmentalfield,and recently applied in energy storage.Seed-assisted synthesis is a very effective approach in promoting the crystallization of zeolites.In some cases,the target zeolite cannot be formed in the absence of seed zeolite.In homologous seed-assisted synthesis,the structure of the seed zeolite is the same to that of the target zeolite,while the structure of the seed zeolite is different to that of the target zeolite in the heterologous seed-assisted synthesis.In this review,we briefly summarized the heterologous seed-assisted syntheses of zeolites and analyzed the structure-directing effect of heterologous seeds and surveyed the“common composite building units(CBUs)hypothesis”and the“common secondary building units(SBUs)hypothesis”.However,both hypotheses cannot explain all observations on the heterologous seed-assisted syntheses.Finally,we proposed that the formation of the target zeolite does need nuclei with the structure of target zeolite and the formation of the nuclei of the target zeolite can be promoted by either the undissolved seed crystals with the same CBUs or SBUs to the target zeolite or by the facilitated appropriate distribution of the specific building units due to the presence of the heterologous seed that does not have any common CBUs and SBUs with the target zeolite. 展开更多
关键词 ZEOLITE Heterologous seed synthesis Structure-directing effect
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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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Synthesis and Modulation of Low-Dimensional Transition Metal Chalcogenide Materials via Atomic Substitution 被引量:1
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作者 Xuan Wang Akang Chen +3 位作者 XinLei Wu Jiatao Zhang Jichen Dong Leining Zhang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第9期49-94,共46页
In recent years,low-dimensional transition metal chalcogenide(TMC)materials have garnered growing research attention due to their superior electronic,optical,and catalytic properties compared to their bulk counterpart... In recent years,low-dimensional transition metal chalcogenide(TMC)materials have garnered growing research attention due to their superior electronic,optical,and catalytic properties compared to their bulk counterparts.The controllable synthesis and manipulation of these materials are crucial for tailoring their properties and unlocking their full potential in various applications.In this context,the atomic substitution method has emerged as a favorable approach.It involves the replacement of specific atoms within TMC structures with other elements and possesses the capability to regulate the compositions finely,crystal structures,and inherent properties of the resulting materials.In this review,we present a comprehensive overview on various strategies of atomic substitution employed in the synthesis of zero-dimensional,one-dimensional and two-dimensional TMC materials.The effects of substituting elements,substitution ratios,and substitution positions on the structures and morphologies of resulting material are discussed.The enhanced electrocatalytic performance and photovoltaic properties of the obtained materials are also provided,emphasizing the role of atomic substitution in achieving these advancements.Finally,challenges and future prospects in the field of atomic substitution for fabricating low-dimensional TMC materials are summarized. 展开更多
关键词 Transition metal chalcogenides Atomic substitution Ion exchange Low-dimensional materials Controllable synthesis
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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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Recent advances in cobalt phosphide-based materials for electrocatalytic water splitting:From catalytic mechanism and synthesis method to optimization design 被引量:1
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作者 Rongrong Deng Mengwei Guo +1 位作者 Chaowu Wang Qibo Zhang 《Nano Materials Science》 EI CAS CSCD 2024年第2期139-173,共35页
Electrochemical water splitting has long been considered an effective energy conversion technology for trans-ferring intermittent renewable electricity into hydrogen fuel,and the exploration of cost-effective and high... Electrochemical water splitting has long been considered an effective energy conversion technology for trans-ferring intermittent renewable electricity into hydrogen fuel,and the exploration of cost-effective and high-performance electrocatalysts is crucial in making electrolyzed water technology commercially viable.Cobalt phosphide(Co-P)has emerged as a catalyst of high potential owing to its high catalytic activity and durability in water splitting.This paper systematically reviews the latest advances in the development of Co-P-based materials for use in water splitting.The essential effects of P in enhancing the catalytic performance of the hydrogen evolution reaction and oxygen evolution reaction are first outlined.Then,versatile synthesis techniques for Co-P electrocatalysts are summarized,followed by advanced strategies to enhance the electrocatalytic performance of Co-P materials,including heteroatom doping,composite construction,integration with well-conductive sub-strates,and structure control from the viewpoint of experiment.Along with these optimization strategies,the understanding of the inherent mechanism of enhanced catalytic performance is also discussed.Finally,some existing challenges in the development of highly active and stable Co-P-based materials are clarified,and pro-spective directions for prompting the wide commercialization of water electrolysis technology are proposed. 展开更多
关键词 Co-P electrocatalysts Water splitting Hydrogen production Catalytic mechanism synthesis technique Optimization design
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Metagenomic analysis revealing the metabolic role of microbial communities in the free amino acid biosynthesis of Monascus rice vinegar during fermentation 被引量:1
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作者 Hang Gao Jian Zhang +4 位作者 Li Liu Lijun Fu Yan Zhao Germán Mazza Xin Zhang 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第4期2317-2326,共10页
Free amino acid(FAA)is the important component of vinegar that infl uences quality perception and consumer acceptance.FAA is one of the major metabolites produced by microorganisms;however,the microbial metabolic netw... Free amino acid(FAA)is the important component of vinegar that infl uences quality perception and consumer acceptance.FAA is one of the major metabolites produced by microorganisms;however,the microbial metabolic network on FAA biosynthesis remains unclear.Through metagenomic analysis,this work aimed to elucidate the roles of microbes in FAA biosynthesis during Monascus rice vinegar fermentation.Taxonomic profiles from functional analyses showed 14 dominant genera with high contributions to the metabolism pathways.The metabolic network for FAA biosynthesis was then constructed,and the microbial distribution in different metabolic pathways was illuminated.The results revealed that 5 functional genera were closely involved in FAA biosynthesis.This study illuminated the metabolic roles of microorganisms in FAA biosynthesis and provided crucial insights into the functional attributes of microbiota in vinegar fermentation. 展开更多
关键词 Monascus rice vinegar Metagenomic analysis Free amino acid synthesis Metabolic pathway Microbial distribution
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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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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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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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Nucleosynthesis in the little bang
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作者 Marcus Bleicher 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第8期1-4,共4页
A new approach based on relativistic kinetic equations is proposed to solve the long-standing puzzle of light cluster formation, also called nucleosynthesis, in high-energy heavy-ion collisions. This method addresses ... A new approach based on relativistic kinetic equations is proposed to solve the long-standing puzzle of light cluster formation, also called nucleosynthesis, in high-energy heavy-ion collisions. This method addresses the tension between STAR data and previous studies relying on either statistical equilibrium or coalescence approaches. 展开更多
关键词 synthesis RELATIVISTIC CLUSTER
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N,S,Br co-doped carbon dots:One-step synthesis and fluorescent detection of 6-mercaptopurine in tablet
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作者 Qi Wang Ying Cheng +4 位作者 Lifeng Ding Shengling Li Jie Zhang Yulan Niu Ziye Jing 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2024年第2期291-293,共3页
6-mercaptopurine(6-MP),a purine derivative(3,7-dihydropurine-6-thione),has been utilized as an effective immunosuppressive drug for clinically treating leukemia and other autoimmune diseases[1].6-MP and its correspond... 6-mercaptopurine(6-MP),a purine derivative(3,7-dihydropurine-6-thione),has been utilized as an effective immunosuppressive drug for clinically treating leukemia and other autoimmune diseases[1].6-MP and its corresponding metabolites can suppress the function of RnaseH,and thus they are cytotoxic and threaten the human health[2].Therefore,the accurate quantification of 6-MP is crucial.To date,researchers continue to expend considerable effort in developing 6-MP detection methods.Fluorescence analysis eliminates disadvantages,such as toxic solvents,expensive equipment. 展开更多
关键词 PURINE synthesis eliminate
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Synthesis Methods and Property Control of Two-Dimensional Magnetic Materials
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作者 李明爽 李惠敏 刘松 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第2期112-121,共10页
Two-dimensional(2D)magnetic materials have been demonstrated to have excellent chemical,optical,electrical,and magnetic properties,particularly in the development of multifunctional electronic and spin electronic devi... Two-dimensional(2D)magnetic materials have been demonstrated to have excellent chemical,optical,electrical,and magnetic properties,particularly in the development of multifunctional electronic and spin electronic devices,showcasing tremendous potential.Therefore,corresponding synthesis techniques for 2D magnetic materials that offer high quality,high yield,low cost,time-saving,and simplicity are highly desired.This review provides a comprehensive overview of recent research advances in preparation of magnetic 2D materials,with a particular focus on the preparation methods employed.Moreover,the characteristics and applications of these magnetic materials are also discussed.Finally,the challenges and prospects of synthesis methods for magnetic 2D materials are briefly addressed.This review serves as a guiding reference for the controlled synthesis of 2D magnetic materials. 展开更多
关键词 synthesis PREPARATION SIMPLICITY
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Synthesis of mordenite by solvent-free method and its application in the dimethyl ether carbonylation reaction
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作者 Yinghui Liu Shaoduo Liu +8 位作者 Xiaosheng Wang Hongjing Wang Ranjia Li Changchun Yu Chunming Xu Yuxiang Liu Zhengqiu Xie Yongqiang Wang Pan Tang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第2期216-223,共8页
Mordenite with different Si/Al ratios were synthesized by solvent-free method and used for dimethyl ether(DME)carbonylation reaction.The influence of Si/Al ratio in the feedstock on the structure,porosity and acid sit... Mordenite with different Si/Al ratios were synthesized by solvent-free method and used for dimethyl ether(DME)carbonylation reaction.The influence of Si/Al ratio in the feedstock on the structure,porosity and acid sites were systematically investigated.The characterization results showed that with the increase of Si/Al ratio in the feedstock,part of silicon species fail to enter the skeleton and the specific surface area and pore volume of the samples decreased.The amount of weak acid and medium strong acid decreased alongside with the increasing Si/Al ratio,and the amount of strong acid slightly increased.The Al atoms preferentially enter the strong acid sites in the 8 member ring(MR)channel during the crystallization process.The high Si/Al ratio sample had more acid sites located in the 8 MR channel,leading to more active sites for carbonylation reaction and higher catalytic performance.Appropriately increasing the Si/Al ratio was beneficial for the improvement of carbonylation reaction activity over the mordenite(MOR)catalyst. 展开更多
关键词 CARBONYLATION Dimethyl ether SOLVENT-FREE ZEOLITE synthesis CATALYSIS
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Synthesis of Silver Nanoparticles from Honeybees and Its Antibacterial Potential
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作者 Akamu J. Ewunkem Niore’s Johnson +3 位作者 A’lyiha F. Beard Ilunga Tshimanga Brittany Justice Jeffery Meixner 《Open Journal of Medical Microbiology》 2024年第1期77-92,共16页
Honeybees (Apis mellifera) are important pollinators of flowering plants and agricultural crops contributing annually to billions of dollars in revenues to crop production. Honeybees have an average lifespan between 8... Honeybees (Apis mellifera) are important pollinators of flowering plants and agricultural crops contributing annually to billions of dollars in revenues to crop production. Honeybees have an average lifespan between 8 weeks to 5 years. Dead honeybees are abundantly available in beehives and can be utilized as an alternative source to synthesize nanoparticles. In recent years, biologically synthesized nanoparticles have been preferred over their chemical counterparts. However, honeybee-based-green synthesis of nanoparticles has not been explored yet. Herein, we report the biosynthesis of silver nanoparticles from honeybees and its antibacterial activity. The synthesis of silver nanoparticles was monitored visually through a gradual change in color. Furthermore, the biosynthesized nanoparticles were confirmed and characterized by UV-visible spectroscopy. Scanning Electron Microscope was utilized to analyze the average size and morphologies of the biosynthesized nanoparticles. Subsequently, the antibacterial potential of the biosynthesized silver nanoparticles was tested against selected Gram-positive and Gram-negative bacterial strains. It was found that a distinct color change from yellow to brown in the reaction solution suggested the formation of silver nanoparticles. The biosynthesized nanoparticles exhibited absorption maxima at 430 nm. The SEM analysis confirmed the spherical and cuboidal shape of the biosynthesized silver nanoparticles with a size range between 10 - 40 nm. Furthermore, the biosynthesized silver nanoparticles exhibited strong antimicrobial potential against tested Gram-positive and Gram-negative bacteria strains by aggregating on the cell surface. This study showcases the biomedical and agricultural applications of biosynthesized silver nanoparticles from honeybee wings. . 展开更多
关键词 HONEYBEE BACTERIA Green synthesis Nanoparticles ANTIMICROBIAL
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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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Transcriptomic and metabolomic analysis provides insights into lignin biosynthesis and accumulation and differences in lodging resistance in hybrid wheat
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作者 Weibing Yang Shengquan Zhang +7 位作者 Qiling Hou Jiangang Gao Hanxia Wang Xianchao Chen Xiangzheng Liao Fengting Zhang Changping Zhao Zhilie Qin 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第4期1105-1117,共13页
The use of hybrid wheat is one way to improve the yield in the future.However,greater plant heights increase lodging risk to some extent.In this study,two hybrid combinations with differences in lodging resistance wer... The use of hybrid wheat is one way to improve the yield in the future.However,greater plant heights increase lodging risk to some extent.In this study,two hybrid combinations with differences in lodging resistance were used to analyze the stem-related traits during the filling stage,and to investigate the mechanism of the difference in lodging resistance by analyzing lignin synthesis of the basal second internode(BSI).The stem-related traits such as the breaking strength,stem pole substantial degree(SPSD),and rind penetration strength(RPS),as well as the lignin content of the lodging-resistant combination(LRC),were significantly higher than those of the lodgingsensitive combination(LSC).The phenylpropanoid biosynthesis pathway was significantly and simultaneously enriched according to the transcriptomics and metabolomics analysis at the later filling stage.A total of 35 critical regulatory genes involved in the phenylpropanoid pathway were identified.Moreover,42%of the identified genes were significantly and differentially expressed at the later grain-filling stage between the two combinations,among which more than 80%were strongly up-regulated at that stage in the LRC compared with LSC.On the contrary,the LRC displayed lower contents of lignin intermediate metabolites than the LSC.These results suggested that the key to the lodging resistance formation of LRC is largely the higher lignin synthesis at the later grain-filling stage.Finally,breeding strategies for synergistically improving plant height and lodging resistance of hybrid wheat were put forward by comparing the LRC with the conventional wheat applied in large areas. 展开更多
关键词 gene expression lignin synthesis lodging-resistance hybrid wheat
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Study on trifluoromethanesulfonic acid-promoted synthesis of daidzein: Process optimization and reaction mechanism
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作者 Hai Cao Haibin Yang +3 位作者 Yanxiong Fang Yuandi Zeng Xiaolan Cai Jingjing Ma 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第7期132-139,共8页
Daidzein has been widely used in pharmaceuticals,nutraceuticals,cosmetics,feed additives,etc.Its preparation process and related reaction mechanism need to be further investigated.A cost-effective process for synthesi... Daidzein has been widely used in pharmaceuticals,nutraceuticals,cosmetics,feed additives,etc.Its preparation process and related reaction mechanism need to be further investigated.A cost-effective process for synthesizing daidzein was developed in this work.In this article,a two-step synthesis of daidzein(Friedel–Crafts acylation and[5+1]cyclization)was developed via the employment of trifluoromethanesulfonic acid(TfOH)as an effective promoting reagent.The effect of reaction conditions such as solvent,the amount of TfOH,reaction temperature,and reactant ratio on the conversion rate and the yield of the reaction,respectively,was systematically investigated,and daidzein was obtained in 74.0%isolated yield under optimal conditions.Due to the facilitating effect of TfOH,the Friedel–Crafts acylation was completed within 10 min at 90℃ and the[5+1]cyclization was completed within 180 min at 25℃.In addition,a possible reaction mechanism for this process was proposed.The results of the study may provide useful guidance for industrial production of daidzein on a large scale. 展开更多
关键词 synthesis Optimal design Chemical processes Reaction mechanism
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