Porous SnO2 nanocrystalline thin films were successfully electrodeposited from an oxygen-saturated acid aqueous solution of SnCl2 containing different concentrations of butyl-rhodamine B(BRhB) at 70℃.BRhB with subs...Porous SnO2 nanocrystalline thin films were successfully electrodeposited from an oxygen-saturated acid aqueous solution of SnCl2 containing different concentrations of butyl-rhodamine B(BRhB) at 70℃.BRhB with substitute of amidocyanogen can be dissolved in the acid deposition solution,where HCl was added to suppress hydrolysis of SnCl2.So it was used as a structure-directing agent to promote the crystal growth of SnO_2.The formed porous morphology and tetragonal rutile crystalline structure of the electrodeposited thin films were controlled by the addition of BRhB with different amounts.展开更多
Zeolites have been widely applied in many chemical processes owing to their featured microporous framework structures.Organic structure-directing agents(OSDAs) play an important role during of the formation of zeolite...Zeolites have been widely applied in many chemical processes owing to their featured microporous framework structures.Organic structure-directing agents(OSDAs) play an important role during of the formation of zeolite frameworks via non-bonding host-vip interactions.Understanding these interactions is crucial to the design of OSDAs and the synthesis of target zeolites.Here,we report a molecular simulation study in the host-vip interactions between zeolite framework STW and 21 alkylated imidazolium and pyrazolium cations that have been used as the OSDAs for the synthesis of STW-type zeolites.We find that OSDAs that have successfully directed the formation of STW exhibit stronger host-vip interactions than unsuccessful ones.Furthermore,we find all successful OSDAs possess relatively more negative atomic charges on nitrogen atoms and smaller dipole moments.According to this finding,we have designed seven new alkylated imidazolium and pyrazolium cations that may be suitable for zeolite STW,and verified their structure-directing capability by molecular simulation calculations.展开更多
Zeolite synthesis in contemporary chemical industries is predominantly conducted using organic structure‐directing agents(OSDAs),which are chronically hazardous to humans and the environment.It is a growing trend to ...Zeolite synthesis in contemporary chemical industries is predominantly conducted using organic structure‐directing agents(OSDAs),which are chronically hazardous to humans and the environment.It is a growing trend to develop an eco‐friendly and nuisanceless OSDA for zeolite synthesis.Herein,choline is employed as a non‐toxic and green OSDA to synthesize high silica Y zeolite with SiO2/Al2O3 ratios of 6.5–6.8.The prepared Y zeolite samples exhibited outstanding(hydro)thermal stability at ultrahigh temperature owing to the higher SiO2/Al2O3 ratio.The XRF,SEM,29Si‐NMR and 13Na+results suggested that choline plays a structure‐directing role in the synthesis of Y zeolite,while the feed molar fraction of Na+is a crucial determinant for the framework SiO2/Al2O3 ratio and the crystal morphology.展开更多
We report results from computational modeling of the relative stability of germanosilicate SCM-15 structure due to different distribution of germanium heteroatoms in the double four-member rings(D4Rs)of the framework ...We report results from computational modeling of the relative stability of germanosilicate SCM-15 structure due to different distribution of germanium heteroatoms in the double four-member rings(D4Rs)of the framework and the orientation of the structure directing agent(SDA)molecules in the as-synthesized zeolite.The calculated relative energies of the bare zeolite framework suggest that structures with germanium ions clustered in the same D4Rs,e.g.,with large number of Ge–O-Ge contacts,are the most stable.The simulations of various orientations of the SDA in the pores of the germanosilicate zeolite show different stability order-the most stable models are the structures with germanium spread among all D4Rs.Thus,for SCM-15 the stabilization due to the presence of the SDA and their orientation,is thermodynamic factor directing both the formation of specific framework type and Ge distribution in the framework during the synthesis.The relative stability of bare structures with different germanium distribution is of minor importance.This differs from SCM-14 germanosilicate,reported earlier,for which the stability order is preserved in presence of SDA.Thus,even for zeolites with the same chemical composition and SDA,the characteristics of their framework lead to different energetic preference for germanium distribution.展开更多
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
Melatonin(N-acetyl-5-methoxytryptamine)is known as the hormone of darkness because it is synthesized at night and involved in regulating the circadian clock.The hormone is primarily synthesized by the vertebrate pinea...Melatonin(N-acetyl-5-methoxytryptamine)is known as the hormone of darkness because it is synthesized at night and involved in regulating the circadian clock.The hormone is primarily synthesized by the vertebrate pineal gland,but is ubiquitous among invertebrates,unicellular organisms,plants,and even cyanobacteria(Hattori and Suzuki,2024).Melatonin is well-conserved evolutionarily and possesses several physiological functions,such as immune response,bone and glucose metabolism,and memory formation besides regulating the circadian rhythm.展开更多
Hard carbon(HC)is widely used in sodium-ion batteries(SIBs),but its performance has always been limited by lowinitial Coulombic efficiency(ICE)and cycling stability.Cathode compensation agent is a favorable strategy t...Hard carbon(HC)is widely used in sodium-ion batteries(SIBs),but its performance has always been limited by lowinitial Coulombic efficiency(ICE)and cycling stability.Cathode compensation agent is a favorable strategy to make up for the loss of active sodium ions consumed byHCanode.Yet it lacks agent that effectively decomposes to increase the active sodium ions as well as regulate carbon defects for decreasing the irreversible sodium ions consumption.Here,we propose 1,2-dihydroxybenzene Na salt(NaDB)as a cathode compensation agent with high specific capacity(347.9 mAh g^(-1)),lower desodiation potential(2.4–2.8 V)and high utilization(99%).Meanwhile,its byproduct could functionalize HC with more C=O groups and promote its reversible capacity.Consequently,the presodiation hard carbon(pHC)anode exhibits highly reversible capacity of 204.7 mAh g^(-1) with 98%retention at 5 C rate over 1000 cycles.Moreover,with 5 wt%NaDB initially coated on the Na3V2(PO4)3(NVP)cathode,the capacity retention of NVP + NaDB|HC cell could increase from 22%to 89%after 1000 cycles at 1 C rate.This work provides a new avenue to improve reversible capacity and cycling performance of SIBs through designing functional cathode compensation agent.展开更多
本文根据企业公开信息,收集并整理了国内部分AI Agent应用相关企业。从Chatbots到AI Agents根据OpenAI的定义,通用人工智能(artificial general intelligence,AGI)的终极目标是创造一种能够像人类一样完成各种复杂任务,同时还能自然交...本文根据企业公开信息,收集并整理了国内部分AI Agent应用相关企业。从Chatbots到AI Agents根据OpenAI的定义,通用人工智能(artificial general intelligence,AGI)的终极目标是创造一种能够像人类一样完成各种复杂任务,同时还能自然交流的人工智能(AI)。OpenAI将AGI的发展分成了五个等级:第一级是“聊天机器人”(chatbots),具备语言对话能力的人工智能;第二级是“推理者”(reasoners),具备人类的推理水平,能解决多种复杂难题的人工智能;第三级是“代理人”(agents)。展开更多
基金supported by the National Natural Science Foundation of China(Nos.20873162,50872007)the State Key Laboratory of Pollution Control and Resource Reuse Foundation(No.PCRRF09006)Beijing Natural Science Foundation(No.8092022).
文摘Porous SnO2 nanocrystalline thin films were successfully electrodeposited from an oxygen-saturated acid aqueous solution of SnCl2 containing different concentrations of butyl-rhodamine B(BRhB) at 70℃.BRhB with substitute of amidocyanogen can be dissolved in the acid deposition solution,where HCl was added to suppress hydrolysis of SnCl2.So it was used as a structure-directing agent to promote the crystal growth of SnO_2.The formed porous morphology and tetragonal rutile crystalline structure of the electrodeposited thin films were controlled by the addition of BRhB with different amounts.
基金the National Natural Science Foundation of China(Nos.21622102,21621001 and 21920102005)the National Key Research and Development Program of China(No.2016YFB0701100)+1 种基金the National 111 Project(No.B17020)Program for JLUSTIRT and High Performance Computing Center of Jilin University。
文摘Zeolites have been widely applied in many chemical processes owing to their featured microporous framework structures.Organic structure-directing agents(OSDAs) play an important role during of the formation of zeolite frameworks via non-bonding host-vip interactions.Understanding these interactions is crucial to the design of OSDAs and the synthesis of target zeolites.Here,we report a molecular simulation study in the host-vip interactions between zeolite framework STW and 21 alkylated imidazolium and pyrazolium cations that have been used as the OSDAs for the synthesis of STW-type zeolites.We find that OSDAs that have successfully directed the formation of STW exhibit stronger host-vip interactions than unsuccessful ones.Furthermore,we find all successful OSDAs possess relatively more negative atomic charges on nitrogen atoms and smaller dipole moments.According to this finding,we have designed seven new alkylated imidazolium and pyrazolium cations that may be suitable for zeolite STW,and verified their structure-directing capability by molecular simulation calculations.
基金supported by the National Natural Science Foundation of China(Grant No.21802136)~~
文摘Zeolite synthesis in contemporary chemical industries is predominantly conducted using organic structure‐directing agents(OSDAs),which are chronically hazardous to humans and the environment.It is a growing trend to develop an eco‐friendly and nuisanceless OSDA for zeolite synthesis.Herein,choline is employed as a non‐toxic and green OSDA to synthesize high silica Y zeolite with SiO2/Al2O3 ratios of 6.5–6.8.The prepared Y zeolite samples exhibited outstanding(hydro)thermal stability at ultrahigh temperature owing to the higher SiO2/Al2O3 ratio.The XRF,SEM,29Si‐NMR and 13Na+results suggested that choline plays a structure‐directing role in the synthesis of Y zeolite,while the feed molar fraction of Na+is a crucial determinant for the framework SiO2/Al2O3 ratio and the crystal morphology.
文摘We report results from computational modeling of the relative stability of germanosilicate SCM-15 structure due to different distribution of germanium heteroatoms in the double four-member rings(D4Rs)of the framework and the orientation of the structure directing agent(SDA)molecules in the as-synthesized zeolite.The calculated relative energies of the bare zeolite framework suggest that structures with germanium ions clustered in the same D4Rs,e.g.,with large number of Ge–O-Ge contacts,are the most stable.The simulations of various orientations of the SDA in the pores of the germanosilicate zeolite show different stability order-the most stable models are the structures with germanium spread among all D4Rs.Thus,for SCM-15 the stabilization due to the presence of the SDA and their orientation,is thermodynamic factor directing both the formation of specific framework type and Ge distribution in the framework during the synthesis.The relative stability of bare structures with different germanium distribution is of minor importance.This differs from SCM-14 germanosilicate,reported earlier,for which the stability order is preserved in presence of SDA.Thus,even for zeolites with the same chemical composition and SDA,the characteristics of their framework lead to different energetic preference for germanium distribution.
基金support from the National Key Research and Development Program of China(2021YFA1500401,2021YFA1501202)the National Natural Science Foundation of China(22288101)the 111 Project(B17020)for supporting this work.
文摘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.
基金supported by JSPS KAKENHI Grant Number JP22K11823 to AH and JP22J01508 to KW。
文摘Melatonin(N-acetyl-5-methoxytryptamine)is known as the hormone of darkness because it is synthesized at night and involved in regulating the circadian clock.The hormone is primarily synthesized by the vertebrate pineal gland,but is ubiquitous among invertebrates,unicellular organisms,plants,and even cyanobacteria(Hattori and Suzuki,2024).Melatonin is well-conserved evolutionarily and possesses several physiological functions,such as immune response,bone and glucose metabolism,and memory formation besides regulating the circadian rhythm.
基金supported by National Natural Science Foundation of China(No.22278308 and 22109114)Open Foundation of Shanghai Jiao Tong University Shaoxing Research Institute of Renewable Energy and Molecular Engineering(Grant number:JDSX2022023).
文摘Hard carbon(HC)is widely used in sodium-ion batteries(SIBs),but its performance has always been limited by lowinitial Coulombic efficiency(ICE)and cycling stability.Cathode compensation agent is a favorable strategy to make up for the loss of active sodium ions consumed byHCanode.Yet it lacks agent that effectively decomposes to increase the active sodium ions as well as regulate carbon defects for decreasing the irreversible sodium ions consumption.Here,we propose 1,2-dihydroxybenzene Na salt(NaDB)as a cathode compensation agent with high specific capacity(347.9 mAh g^(-1)),lower desodiation potential(2.4–2.8 V)and high utilization(99%).Meanwhile,its byproduct could functionalize HC with more C=O groups and promote its reversible capacity.Consequently,the presodiation hard carbon(pHC)anode exhibits highly reversible capacity of 204.7 mAh g^(-1) with 98%retention at 5 C rate over 1000 cycles.Moreover,with 5 wt%NaDB initially coated on the Na3V2(PO4)3(NVP)cathode,the capacity retention of NVP + NaDB|HC cell could increase from 22%to 89%after 1000 cycles at 1 C rate.This work provides a new avenue to improve reversible capacity and cycling performance of SIBs through designing functional cathode compensation agent.
文摘本文根据企业公开信息,收集并整理了国内部分AI Agent应用相关企业。从Chatbots到AI Agents根据OpenAI的定义,通用人工智能(artificial general intelligence,AGI)的终极目标是创造一种能够像人类一样完成各种复杂任务,同时还能自然交流的人工智能(AI)。OpenAI将AGI的发展分成了五个等级:第一级是“聊天机器人”(chatbots),具备语言对话能力的人工智能;第二级是“推理者”(reasoners),具备人类的推理水平,能解决多种复杂难题的人工智能;第三级是“代理人”(agents)。