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Aqueous electrochemical delithiation of cathode materials as a strategy to selectively recover lithium from waste lithium-ion batteries
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作者 Pier Giorgio Schiavi Andrea Giacomo Marrani +4 位作者 Olga Russina Ludovica D’Annibale Francesco Amato Francesca Pagnanelli Pietro Altimari 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第1期144-153,I0004,共11页
Lithium recovery from end-of-life Li-ion batteries(LIBs)through pyro-and hydrometallurgical recycling processes involves several refining stages,with high consumption of reagents and energy.A competitive technological... Lithium recovery from end-of-life Li-ion batteries(LIBs)through pyro-and hydrometallurgical recycling processes involves several refining stages,with high consumption of reagents and energy.A competitive technological alternative is the electrochemical oxidation of the cathode materials,whereby lithium can be deintercalated and transferred to an electrolyte solution without the aid of chemical extracting compounds.This article investigates the potential to selectively recover Li from LIB cathode materials by direct electrochemical extraction in aqueous solutions.The process allowed to recovering up to 98%of Li from high-purity commercial cathode materials(LiMn_(2)O_(4),LiCoO_(2),and Li Ni_(1/3)Mn_(1/3)Co_(1/3)O_(2))with a faradaic efficiency of 98%and negligible co-extraction of Co,Ni,and Mn.The process was then applied to recover Li from the real waste LIBs black mass obtained by the physical treatment of electric vehicle battery packs.This black mass contained graphite,conductive carbon,and metal impurities from current collectors and steel cases,which significantly influenced the evolution and performances of Li electrochemical extraction.Particularly,due to concomitant oxidation of impurities,lithium extraction yields and faradaic efficiencies were lower than those obtained with high-purity cathode materials.Copper oxidation was found to occur within the voltage range investigated,but it could not quantitatively explain the reduced Li extraction performances.In fact,a detailed investigation revealed that above 1.3 V vs.Ag/Ag Cl,conductive carbon can be oxidized,contributing to the decreased Li extraction.Based on the reported experimental results,guidelines were provided that quantitatively enable the extraction of Li from the black mass,while preventing the simultaneous oxidation of impurities and,consequently,reducing the energy consumption of the proposed Li recovery method. 展开更多
关键词 Lithium recovery Lithium-ion batteries recycling Electrochemical lithium extraction Lithium selective EXTRACTION
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Dealuminated Hβ zeolite for selective conversion of fructose to furfural and formic acid 被引量:1
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作者 Rui Li Qixuan Lin +3 位作者 Junli Ren Xiaobao Yang Yingxiong Wang Lingzhao Kong 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第2期311-320,共10页
The fructose-to-furfural transformation is facing major challenges in the selectivity and high efficiency. Herein, we have developed a simple and effective approach for the selective conversion of fructose to furfural... The fructose-to-furfural transformation is facing major challenges in the selectivity and high efficiency. Herein, we have developed a simple and effective approach for the selective conversion of fructose to furfural using Hβ zeolite modified by organic acids for dealuminization to regulate its textural and acidic properties. It was found that citric acid-dealuminized Hβ zeolite possessed high specific surface areas, wide channels and high Brønsted acid amount, which facilitated the selective conversion of fructose to furfural with a maximum yield of 76.2% at433 K for 1 h in the γ-butyrolactone(GBL)-H_(2)O system, as well as the concomitant formation of 83.0% formic acid. The^(13)C-isotope labelling experiments and the mechanism revealed that the selective cleavage of C1–C2 or C5–C6 bond on fructose was firstly occurred to form pentose or C5 intermediate by weak Brønsted acid, which was then dehydrated to furfural by strong Brønsted acid. Also this dealuminized Hβ catalyst showed the great recycling performance and was active for the conversion of glucose and mannose. 展开更多
关键词 FRUCTOSE Dealuminated-Hb zeolite selective conversion FURFURAL
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Strategies of selective electroreduction of aqueous nitrate to N_(2) in chloride-free system:A critical review
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作者 Fukuan Li Weizhe Zhang +2 位作者 Peng Zhang Ao Gong Kexun Li 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第2期198-216,共19页
Electroreduction of nitrate has been gaining wide attention in recent years owing to it's beneficial for converting nitrate into benign N_(2) from the perspective of electrocatalytic denitrification or into value-... Electroreduction of nitrate has been gaining wide attention in recent years owing to it's beneficial for converting nitrate into benign N_(2) from the perspective of electrocatalytic denitrification or into value-added ammonia from the perspective of electrocatalytic NH_(3) synthesis.By reason of the undesired formation of ammonia is dominant during electroreduction of nitrate-containing wastewater,chloride has been widely used to improve N_(2) selectivity.Nevertheless,selective electroreduction of nitrate to N2 gas in chloride-containing system poses several drawbacks.In this review,we focus on the key strategies for efficiently enhancing N_(2) selectivity of electroreduction of nitrate in chloride-free system,including optimal selection of elements,combining an active metal catalyst with another metal,manipulating the crystalline morphology and facet orientation,constructing core–shell structure catalysts,etc.Before summarizing the strategies,four possible reaction pathways of electro-reduction of nitrate to N_(2) are discussed.Overall,this review attempts to provide practical strategies for enhancing N2 selectivity without the aid of electrochlorination and highlight directions for future research for designing appropriate electrocatalyst for final electrocatalytic denitrifi-cation. 展开更多
关键词 NITRATE CHLORIDE ELECTROREDUCTION SELECTIVITY NITROGEN
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Cell-type resolved transcriptomic approaches for dissecting selective vulnerability in neurodgeneration
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作者 Caleb A.Wood Nicholas M.Tran 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第7期1411-1413,共3页
A common feature among neurodegenerative conditions is that ce rtain neuronal populations are selectively vulnerable to loss(Fu et al.,2018).By corollary,other neurons are selectively resilient,suggesting they may pos... A common feature among neurodegenerative conditions is that ce rtain neuronal populations are selectively vulnerable to loss(Fu et al.,2018).By corollary,other neurons are selectively resilient,suggesting they may possess unique features that support their survival.U nderstanding the basis of neuronal resilience or vulnerability would provide a logical strategy to identify factors that could be targeted therapeutically. 展开更多
关键词 selective TARGETED
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Effect of an Airbag-selective Portal Vein Blood Arrester on the Liver after Hepatectomy:A New Technique for Selective Clamping of the Portal Vein
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作者 Ce-xiong FU Xiao-ri QIN +6 位作者 Jin-song CHEN Jie ZHONG Yu-xu XIE Bi-dan LI Qing-qing FU Fang LI Jin-fang ZHENG 《Current Medical Science》 SCIE CAS 2024年第2期380-390,共11页
Objective:A novel technique was explored using an airbag-selective portal vein blood arrester that circumvents the need for an intraoperative assessment of anatomical variations in patients with complex intrahepatic s... Objective:A novel technique was explored using an airbag-selective portal vein blood arrester that circumvents the need for an intraoperative assessment of anatomical variations in patients with complex intrahepatic space-occupying lesions.Methods:Rabbits undergoing hepatectomy were randomly assigned to 4 groups:intermittent portal triad clamping(PTC),intermittent portal vein clamping(PVC),intermittent portal vein blocker with an airbag-selective portal vein blood arrester(APC),and without portal blood occlusion(control).Hepatic ischemia and reperfusion injury were assessed by measuring the 7-day survival rate,blood loss,liver function,hepatic pathology,hepatic inflammatory cytokine infiltration,hepatic malondialdehyde levels,and proliferating cell nuclear antigen levels.Results:Liver damage was substantially reduced in the APC and PVC groups.The APC animals exhibited transaminase levels similar to or less oxidative stress damage and inflammatory hepatocellular injury compared to those exhibited by the PVC animals.Bleeding was significantly higher in the control group than in the other groups.The APC group had less bleeding than the PVC group because of the avoidance of portal vein skeletonization during hepatectomy.Thus,more operative time was saved in the APC group than in the PVC group.Moreover,the total 7-day survival rate in the APC group was higher than that in the PTC group.Conclusion:Airbag-selective portal vein blood arresters may help protect against hepatic ischemia and reperfusion injury in rabbits undergoing partial hepatectomy.This technique may also help prevent liver damage in patients requiring hepatectomy. 展开更多
关键词 HEPATECTOMY portal vein hepatic damage selective clamping
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Synergy of heterogeneous Co/Ni dual atoms enabling selective C-O bond scission of lignin coupling with in-situ N-functionalization
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作者 Baoyu Wang Jinshu Huang +3 位作者 Hongguo Wu Ximing Yan Yuhe Liao Hu Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期16-25,共10页
Selective cleavage of Csp^(2)-OCH_(3)bond in lignin without breaking other types of C-O bonds followed by N-functionalization is fascinating for on-purpose valorization of biomass.Here,a Co/Ni-based dual-atom catalyst... Selective cleavage of Csp^(2)-OCH_(3)bond in lignin without breaking other types of C-O bonds followed by N-functionalization is fascinating for on-purpose valorization of biomass.Here,a Co/Ni-based dual-atom catalyst CoNiDA@NC prepared by in-situ evaporation and acid-etching of metal species from tailor-made metal–organic frameworks was efficient for reductive upgrading of various lignin-derived phenols to cyclohexanols(88.5%–99.9%yields),which had ca.4 times higher reaction rate than the single-atom catalyst and was superior to state-of-the-art heterogeneous catalysts.The synergistic catalysis of Co/Ni dual atoms facilitated both hydrogen dissociation and hydrogenolysis steps,and could optimize adsorption configuration of lignin-derived methoxylated phenols to further favor the Csp^(2)-OCH_(3)cleavage,as elaborated by theoretical calculations.Notably,the CoNi_(DA)@NC catalyst was highly recyclable,and exhibited excellent demethoxylation performance(77.1%yield)in real lignin monomer mixtures.Via in-situ cascade conversion processes assisted by dual-atom catalysis,various high-value N-containing chemicals,including caprolactams and cyclohexylamines,could be produced from lignin. 展开更多
关键词 Biomass conversion Heterogeneous catalysis LIGNIN Dual-atom catalyst selective C-ocleavage
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Mechanism of selective laser trabeculoplasty:a systemic review
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作者 Yu-Feng Chen Wen Zeng 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第5期963-968,共6页
Although selective laser trabeculoplasty(SLT)is a recognized method for the treatment of glaucoma,the exact changes in the target tissue and mechanism for its intraocular pressure lowing effect are still unclear.The p... Although selective laser trabeculoplasty(SLT)is a recognized method for the treatment of glaucoma,the exact changes in the target tissue and mechanism for its intraocular pressure lowing effect are still unclear.The purpose of this review is to summarize the potential mechanisms of SLT on trabecular meshwork both in vivo and in vitro,so as to reveal the potential mechanism of SLT.SLT may induce immune or inflammatory response in trabecular meshwork(TM)induced by possible oxidative damage etc,and remodel extracellular matrix.It may also induce monocytes to aggregate in TM tissue,increase Schlemm’s canal(SC)cell conductivity,disintegrate cell junction and promote permeability through autocrine and paracrine forms.This provides a theoretical basis for SLT treatment in glaucoma. 展开更多
关键词 MECHANISMS selective laser trabeculoplasty GLAUCOMA trabecular meshwork
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Non-Targeted Metabolomics Reveals the Metabolic Alterations in Response to Artificial Selective Breeding in the Fast-Growing Strains of Pacific Oyster
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作者 HU Boyang TIAN Yuan +1 位作者 LIU Shikai LI Qi 《Journal of Ocean University of China》 CAS CSCD 2024年第2期518-528,共11页
Pacific oyster(Crassostrea gigas)is one of the most important mollusks cultured all around the world.Selective breeding programs of Pacific oysters in China is initiated since 2006 and developed the genetically improv... Pacific oyster(Crassostrea gigas)is one of the most important mollusks cultured all around the world.Selective breeding programs of Pacific oysters in China is initiated since 2006 and developed the genetically improved strain with fast-growing trait.However,little is known about the metabolic signatures of the fast-growing trait.In the present study,the non-targeted metabolomics was performed to analyze the metabolic signatures of adductor muscle tissue in one-year old Pacific oysters from fast-growing strain and the wild population.A total of 7767 and 10174 valid peaks were extracted and quantified in ESI^(+)and ESI^(−)modes,resulting in 399 and 381 annotated metabolites,respectively.PCA and OPLS-DA revealed that considerable separation among samples from fastgrowing strain and wild population,suggesting the differences in metabolic signatures.Meanwhile,81 significantly different metabolites(SDMs)were identified in the comparisons between fast-growing strain and wild population,based on the strict thresholds.It was found that there were highly correlation and conserved coordination among these SDMs.KEGG enrichment analysis indicated that the SDMs were tightly related to pantothenate and CoA biosynthesis,steroid hormone biosynthesis,riboflavin metabolism,and arginine and proline metabolism.Of them,the CoA biosynthesis and metabolism,affected by pantetheine and pantothenic acid,might be important for the growth of Pacific oysters under artificial selective breeding.The study provides the comprehensive views of metabolic signatures in response to artificially selective breeding,and is helpful to better understand the molecular mechanism of fastgrowing traits in Pacific oysters. 展开更多
关键词 metabolic signature Pacific oyster artificial selection fast-growing trait
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Recent developments in selective laser processes for wearable devices
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作者 Youngchan Kim Eunseung Hwang +3 位作者 Chang Kai Kaichen Xu Heng Pan Sukjoon Hong 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2024年第4期517-547,共31页
Recently,the increasing interest in wearable technology for personal healthcare and smart virtual/augmented reality applications has led to the development of facile fabrication methods.Lasers have long been used to d... Recently,the increasing interest in wearable technology for personal healthcare and smart virtual/augmented reality applications has led to the development of facile fabrication methods.Lasers have long been used to develop original solutions to such challenging technological problems due to their remote,sterile,rapid,and site-selective processing of materials.In this review,recent developments in relevant laser processes are summarized under two separate categories.First,transformative approaches,such as for laser-induced graphene,are introduced.In addition to design optimization and the alteration of a native substrate,the latest advances under a transformative approach now enable more complex material compositions and multilayer device configurations through the simultaneous transformation of heterogeneous precursors,or the sequential addition of functional layers coupled with other electronic elements.In addition,the more conventional laser techniques,such as ablation,sintering,and synthesis,can still be used to enhance the functionality of an entire system through the expansion of applicable materials and the adoption of new mechanisms.Later,various wearable device components developed through the corresponding laser processes are discussed,with an emphasis on chemical/physical sensors and energy devices.In addition,special attention is given to applications that use multiple laser sources or processes,which lay the foundation for the all-laser fabrication of wearable devices. 展开更多
关键词 selective laser process Wearable device Transformative approach Laser-induced graphene Ablation SINTERING Synthesis
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Effects of processing parameters on fabrication defects,microstructure and mechanical properties of additive manufactured Mg–Nd–Zn–Zr alloy by selective laser melting process
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作者 Wenyu Xu Penghuai Fu +4 位作者 Nanqing Wang Lei Yang Liming Peng Juan Chen Wenjiang Ding 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第6期2249-2266,共18页
Mg–3Nd–0.2Zn–0.4Zr(NZ30K,wt.%)alloy is a new kind of high-performance metallic biomaterial.The combination of the NZ30K Magnesium(Mg)alloy and selective laser melting(SLM)process seems to be an ideal solution to pr... Mg–3Nd–0.2Zn–0.4Zr(NZ30K,wt.%)alloy is a new kind of high-performance metallic biomaterial.The combination of the NZ30K Magnesium(Mg)alloy and selective laser melting(SLM)process seems to be an ideal solution to produce porous Mg degradable implants.However,the microstructure evolution and mechanical properties of the SLMed NZ30K Mg alloy were not yet studied systematically.Therefore,the fabrication defects,microstructure,and mechanical properties of the SLMed NZ30K alloy under different processing parameters were investigated.The results show that there are two types of fabrication defects in the SLMed NZ30K alloy,gas pores and unfused defects.With the increase of the laser energy density,the porosity sharply decreases to the minimum first and then slightly increases.The minimum porosity is 0.49±0.18%.While the microstructure varies from the large grains with lamellar structure inside under low laser energy density,to the large grains with lamellar structure inside&the equiaxed grains&the columnar grains under middle laser energy density,and further to the fine equiaxed grains&the columnar grains under high laser energy density.The lamellar structure in the large grain is a newly observed microstructure for the NZ30K Mg alloy.Higher laser energy density leads to finer grains,which enhance all the yield strength(YS),ultimate tensile strength(UTS)and elongation,and the best comprehensive mechanical properties obtained are YS of 266±2.1 MPa,UTS of 296±5.2 MPa,with an elongation of 4.9±0.68%.The SLMed NZ30K Mg alloy with a bimodal-grained structure consisting of fine equiaxed grains and coarser columnar grains has better elongation and a yield drop phenomenon. 展开更多
关键词 selective laser melting Mg alloy Processing parameter Lamellar structure Bimodal-grained structure
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A Selective‑Response Hypersensitive Bio‑Inspired Strain Sensor Enabled by Hysteresis Effect and Parallel Through‑Slits Structures
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作者 Qun Wang Zhongwen Yao +8 位作者 Changchao Zhang Honglie Song Hanliang Ding Bo Li Shichao Niu Xinguan Huang Chuanhai Chen Zhiwu Han Luquan Ren 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第2期139-153,共15页
Flexible strain sensors are promising in sensing minuscule mechanical signals,and thereby widely used in various advanced fields.However,the effective integration of hypersensitivity and highly selective response into... Flexible strain sensors are promising in sensing minuscule mechanical signals,and thereby widely used in various advanced fields.However,the effective integration of hypersensitivity and highly selective response into one flexible strain sensor remains a huge challenge.Herein,inspired by the hysteresis strategy of the scorpion slit receptor,a bio-inspired flexible strain sensor(BFSS)with parallel through-slit arrays is designed and fabricated.Specifically,BFSS consists of conductive monolayer graphene and viscoelastic styrene–isoprene–styrene block copolymer.Under the synergistic effect of the bio-inspired slit structures and flexible viscoelastic materials,BFSS can achieve both hypersensitivity and highly selective frequency response.Remarkably,the BFSS exhibits a high gage factor of 657.36,and a precise identification of vibration frequencies at a resolution of 0.2 Hz through undergoing different morphological changes to high-frequency vibration and low-frequency vibration.Moreover,the BFSS possesses a wide frequency detection range(103 Hz)and stable durability(1000 cycles).It can sense and recognize vibration signals with different characteristics,including the frequency,amplitude,and waveform.This work,which turns the hysteresis effect into a"treasure,"can provide new design ideas for sensors for potential applications including human–computer interaction and health monitoring of mechanical equipment. 展开更多
关键词 Bio-inspired strain sensors Hysteresis effect HYPERSENSITIVITY selective frequency response Health monitoring applications
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Inhibition of hepatitis B virus via selective apoptosis modulation by Chinese patent medicine Liuweiwuling Tablet
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作者 Fei-Lin Ge Yan Yang +7 位作者 Lan-Lan Si Yuan-Hua Li Meng-Zhen Cao Jun Wang Zhao-Fang Bai Zhi-Gang Ren Xiao-He Xiao Yan Liu 《World Journal of Gastroenterology》 SCIE CAS 2024年第13期1911-1925,共15页
BACKGROUND Liuweiwuling Tablet(LWWL)is a Chinese patent medicine approved for the treatment of chronic inflammation caused by hepatitis B virus(HBV)infection.Previous studies have indicated an anti-HBV effect of LWWL,... BACKGROUND Liuweiwuling Tablet(LWWL)is a Chinese patent medicine approved for the treatment of chronic inflammation caused by hepatitis B virus(HBV)infection.Previous studies have indicated an anti-HBV effect of LWWL,specifically in terms of antigen inhibition,but the underlying mechanism remains unclear.AIM To investigate the potential mechanism of action of LWWL against HBV.METHODS In vitro experiments utilized three HBV-replicating and three non-HBV-replicating cell lines.The in vivo experiment involved a hydrodynamic injectionmediated mouse model with HBV replication.Transcriptomics and metabolomics were used to investigate the underlying mechanisms of action of LWWL.RESULTS In HepG2.1403F cells,LWWL(0.8 mg/mL)exhibited inhibitory effects on HBV DNA,hepatitis B surface antigen and pregenomic RNA(pgRNA)at rates of 51.36%,24.74%and 50.74%,respectively.The inhibition rates of LWWL(0.8mg/mL)on pgRNA/covalently closed circular DNA in HepG2.1403F,HepG2.2.15 and HepG2.A64 cells were 47.78%,39.51%and 46.74%,respectively.Integration of transcriptomics and metabolomics showed that the anti-HBV effect of LWWL was primarily linked to pathways related to apoptosis(PI3K-AKT,CASP8-CASP3 and P53 pathways).Apoptosis flow analysis revealed that the apoptosis rate in the LWWL-treated group was significantly higher than in the control group(CG)among HBV-replicating cell lines,including HepG2.2.15(2.92%±1.01%vs 6.68%±2.04%,P<0.05),HepG2.A64(4.89%±1.28%vs 8.52%±0.50%,P<0.05)and HepG2.1403F(3.76%±1.40%vs 7.57%±1.35%,P<0.05)(CG vs LWWL-treated group).However,there were no significant differences in apoptosis rates between the non-HBV-replicating HepG2 cells(5.04%±0.74%vs 5.51%±1.57%,P>0.05),L02 cells(5.49%±0.80%vs 5.48%±1.01%,P>0.05)and LX2 cells(6.29%±1.54%vs 6.29%±0.88%,P>0.05).TUNEL staining revealed a significantly higher apoptosis rate in the LWWL-treated group than in the CG in the HBVreplicating mouse model,while no noticeable difference in apoptosis rates between the two groups was observed in the non-HBV-replicating mouse model.CONCLUSION Preliminary results suggest that LWWL exerts a potent inhibitory effect on wild-type and drug-resistant HBV,potentially involving selective regulation of apoptosis.These findings offer novel insights into the anti-HBV activities of LWWL and present a novel mechanism for the development of anti-HBV medications. 展开更多
关键词 Hepatitis B virus Chinese patent medicine Antiviral activity Antiviral mechanism selective apoptosis
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Cu,N codoped carbon nanosheets encapsulating ultrasmall Cu nanoparticles for enhancing selective 1,2-propanediol oxidation
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作者 Yonghai Feng Min Yu +2 位作者 Minjia Meng Lei Liu Dewei Rao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第4期27-35,共9页
In the selective oxidation of biomass-based 1,2-propanediol(PDO)with oxygen as the terminal oxidant,it is challenging to improve the lactic acid(LA)selectivity for nonnoble metal nanoparticles(NPs)due to their limited... In the selective oxidation of biomass-based 1,2-propanediol(PDO)with oxygen as the terminal oxidant,it is challenging to improve the lactic acid(LA)selectivity for nonnoble metal nanoparticles(NPs)due to their limited oxygen reduction rate and easy C-C cleavage.Given the high economic feasibility of nonnoble metals,i.e.,Cu,in this work,copper and nitrogen codoped porous carbon nanosheets encapsulating ultrafine Cu nanoparticles(Cu@Cu-N-C)were developed to realize highly selective of PDO oxidation to LA.The carbon-encapsulated ultrasmall Cu^(0)NPs in Cu@Cu-N-C have high PDO dehydrogenation activity while N-coordinated Cu(Cu-N)sites are responsible for the high oxygen reduction efficacy.Therefore,the performance of catalytic PDO conversion to LA is optimized by a proposed pathway of PDO→hydroxylacetone→lactaldehyde→LA.Specifically,the enhanced LA selectivity is 88.5%,and the PDO conversion is up to 75.1%in an O_(2)-pressurized reaction system(1.0 MPa O_(2)),superior to other Cu-based catalysts,while in a milder nonpressurized system(O_(2)flow rate of 100 mL min-1),a remarkable LA selectivity(94.2%)is obtained with 39.8%PDO conversion,2.2 times higher than that of supported Au nanoparticles(1%Au/C).Moreover,carbon encapsulation offers Cu@Cu-N-C with strong leaching resistance for better recycling. 展开更多
关键词 selective oxidation Copper and nitrogen doped carbon 1 2-PROPANEDIOL Ultrasmall Cu nanoparticles Lactic acid
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Interplay of laser power and pore characteristics in selective laser melting of ZK60 magnesium alloys:A study based on in-situ monitoring and image analysis
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作者 Weijie Xie Hau-Chung Man Chi-Wai Chan 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第4期1346-1366,共21页
This study offers significant insights into the multi-physics phenomena of the SLM process and the subsequent porosity characteristics of ZK60 Magnesium(Mg)alloys.High-speed in-situ monitoring was employed to visualis... This study offers significant insights into the multi-physics phenomena of the SLM process and the subsequent porosity characteristics of ZK60 Magnesium(Mg)alloys.High-speed in-situ monitoring was employed to visualise process signals in real-time,elucidating the dynamics of melt pools and vapour plumes under varying laser power conditions specifically between 40 W and 60 W.Detailed morphological analysis was performed using Scanning-Electron Microscopy(SEM),demonstrating a critical correlation between laser power and pore formation.Lower laser power led to increased pore coverage,whereas a denser structure was observed at higher laser power.This laser power influence on porosity was further confirmed via Optical Microscopy(OM)conducted on both top and cross-sectional surfaces of the samples.An increase in laser power resulted in a decrease in pore coverage and pore size,potentially leading to a denser printed part of Mg alloy.X-ray Computed Tomography(XCT)augmented these findings by providing a 3D volumetric representation of the sample internal structure,revealing an inverse relationship between laser power and overall pore volume.Lower laser power appeared to favour the formation of interconnected pores,while a reduction in interconnected pores and an increase in isolated pores were observed at higher power.The interplay between melt pool size,vapour plume effects,and laser power was found to significantly influence the resulting porosity,indicating a need for effective management of these factors to optimise the SLM process of Mg alloys. 展开更多
关键词 selective laser melting(SLM) Magnesium(Mg)alloys Biodegradable implants POROSITY In-situ monitoring
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Covalency competition induced selective bond breakage and surface reconstruction in manganese cobaltite towards enhanced electrochemical charge storage
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作者 Peng Gao Pei Tang +7 位作者 Ying Mo Peitao Xiao Wang Zhou Shi Chen Hongliang Dong Ziwei Li Chaohe Xu Jilei Liu 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第5期909-918,共10页
Manganese cobaltite(MnCo_(2)_(4))is a promising electrode material because of its attractive redox chemistry and excellent charge storage capability.Our previous work demonstrated that the octahedrally-coordinated Mn ... Manganese cobaltite(MnCo_(2)_(4))is a promising electrode material because of its attractive redox chemistry and excellent charge storage capability.Our previous work demonstrated that the octahedrally-coordinated Mn are prone to react with the hydroxyl ions in alkaline electrolyte upon electrochemical cycling and separates on the surface of spinel to reconstruct into d-MnO_(2) nanosheets irreversibly,thus results in a change of the reaction mechanism with Kþion intercalation.However,the low capacity has greatly limited its practical application.Herein,we found that the tetrahedrally-coordinated Co_(2) þions were leached when MnCo_(2)_(4) was equilibrated in 1 mol L^(-1) HCl solution,leading to the formation of layered CoOOH on MnCo_(2)_(4) surface which is originated from the covalency competition induced selective breakage of the CoT–O bond in CoT–O–CoO and subsequent rearrangement of free Co_(6) octahedra.The as-formed CoOOH is stable upon cycling in alkaline electrolyte,exhibits conversion reaction mechanism with facile proton diffusion and is free of massive structural evolution,thus enables utilization of the bulk electrode material and realizes enhanced specific capacity as well as facilitated charge transfer and ion diffusion.In general,our work not only offers a feasible approach to deliberate modification of MnCo_(2)_(4)'s surface structure,but also provides an in-depth understanding of its charge storage mechanism,which enables rational design of the spinel oxides with promising charge storage properties. 展开更多
关键词 Manganese cobaltite Tetrahedrally-coordinated Co^(2+)leaching selective bond breakage Surface reconstruction Charge storage mechanisms
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Internal electric field modulation by copper vacancy concentration of cuprous sulfide nanosheets for enhanced selective CO_(2) photoreduction
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作者 Xian Shi Weidong Dai +4 位作者 Xiaoqian Li Yang Bai Qin Ren Yao Lei Xing'an Dong 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第4期324-330,共7页
Although the internal electric field(IEF)of photocatalysts is acknowledged as a potent driving force for photocharge separation,modulating the IEF intensity to achieve enhanced photocatalytic performances remains a ch... Although the internal electric field(IEF)of photocatalysts is acknowledged as a potent driving force for photocharge separation,modulating the IEF intensity to achieve enhanced photocatalytic performances remains a challenge.Herein,cuprous sulfide nanosheets with different Cu vacancy concentration were employed to study IEF modulation and corresponding direct charge transfer.Among the samples,Cu_(1.8)S nanosheets possessed intensified IEF intensity compared with those of Cu_(2)S and Cu_(1.95)S nanosheets,suggesting that an enhanced IEF intensity could be achieved by introducing more Cu vacancies.This intensified IEF of Cu_(1.8)S nanosheets induced numerous photogenerated electrons to migrate to its surface,and the dissociative electrons were then captured by Cu vacancies,resulting in efficient charge separation spatially.In addition,the Cu vacancies on Cu_(1.8)S nanosheets accumulated electrons as active sites to lower the energy barrier of rate-determining step of CO_(2)photoreduction,leading to the selective conversion of CO_(2)to CO.Herein,the manipulation of IEF intensity through Cu vacancy concentration regulation of cuprous sulfide photocatalysts for efficient charge separation has been discussed,providing a scientific strategy to rationally improve photocata lytic performances for solar energy conversion. 展开更多
关键词 Internal electric field intensity Cuprous sulfide photocatalysts Cu vacancies Charge separation selective CO_(2) photoreduction
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Ultrasound Ranging with Selective Zone
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作者 Libo Deng 《World Journal of Engineering and Technology》 2024年第2期339-361,共23页
The technology of ultrasonic measurement has been widely applied in many fields in recent years. It has already been researched for almost 40 years and its application in both residential use and military are mature a... The technology of ultrasonic measurement has been widely applied in many fields in recent years. It has already been researched for almost 40 years and its application in both residential use and military are mature and well-developed. One of the advanced uses is for reversing a car and it is based on sending sound waves through a specific medium and observing the returning echoes to measure the distance from the device to the obstacle. In this report, a simple ultrasonic distance measurement system will be introduced including the design of hardware and software, the simulating results and the final product. This system was built to be cheaper, requires less power and delivers better performance. 展开更多
关键词 ULTRASOUND selective Zone
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Safety and efficacy of modified endoscopic ultrasound-guided selective N-butyl-2-cyanoacrylate injections for gastric variceal hemorrhage in left-sided portal hypertension
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作者 Yan Zeng Jian Yang Jun-Wen Zhang 《World Journal of Gastrointestinal Endoscopy》 2024年第1期29-36,共8页
BACKGROUND Gastric variceal hemorrhage is one of the primary manifestations of left-sided portal hypertension(LSPH).The hemorrhage is fatal and requires safe and effective interventions.AIM To evaluate the clinical sa... BACKGROUND Gastric variceal hemorrhage is one of the primary manifestations of left-sided portal hypertension(LSPH).The hemorrhage is fatal and requires safe and effective interventions.AIM To evaluate the clinical safety and efficacy of modified endoscopic ultrasound(EUS)-guided selective N-butyl-2-cyanoacrylate(NBC)injections for gastric variceal hemorrhage in LSPH.METHODS A retrospective observational study of patients with LSPH-induced gastric variceal hemorrhage was conducted.Preoperative EUS evaluations were performed.Enrolled patients were divided into modified and conventional groups according to the NBC injection technique.The final selection of NBC injection technique depended on the patients’preferences and clinical status.The technical and clinical success rates,operation time,NBC doses,perioperative complications,postoperative hospital stay,and recurrent bleeding rates were analyzed,respectively.RESULTS A total of 27 patients were enrolled.No statistically significant differences were observed between the two groups regarding baseline characteristics.In comparison to patients in the conventional group,patients in the modified group demonstrated significantly reduced NBC doses(2.0±0.6 mL vs 3.1±1.0 mL;P=0.004)and increased endoscopic operation time(71.9±11.9 min vs 22.5±6.7 min;P<0.001).Meanwhile,the two groups had no significant difference in the technical and clinical success rates,perioperative complications,postoperative hospital stay,and recurrent bleeding rates.CONCLUSION Modified EUS-guided selective NBC injections demonstrated safety and efficacy for LSPH-induced gastric variceal hemorrhage,with advantages of reduced injection dose and no radiation risk.Drawbacks were time consumption and technical challenge. 展开更多
关键词 Endoscopic ultrasound selective N-butyl-2-cyanoacrylate Gastric varices Hemorrhage Left-sided portal hypertension
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Molecular engineering binuclear copper catalysts for selective CO_(2) reduction to C_(2) products
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作者 Qi Zhao Kai Lei +2 位作者 Bao Yu Xia Rachel Crespo-Otero Devis Di Tommaso 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第6期166-173,I0005,共9页
Molecular copper catalysts serve as exemplary models for correlating the structure-reaction-mechanism relationship in the electrochemical CO_(2) reduction(eCO_(2)R),owing to their adaptable environments surrounding th... Molecular copper catalysts serve as exemplary models for correlating the structure-reaction-mechanism relationship in the electrochemical CO_(2) reduction(eCO_(2)R),owing to their adaptable environments surrounding the copper metal centres.This investigation,employing density functional theory calculations,focuses on a novel family of binuclear Cu molecular catalysts.The modulation of their coordination configuration through the introduction of organic groups aims to assess their efficacy in converting CO_(2) to C_(2)products.Our findings highlight the crucial role of chemical valence state in shaping the characteristics of binuclear Cu catalysts,consequently influencing the eCO_(2)R behaviour,Notably,the Cu(Ⅱ)Cu(Ⅱ)macrocycle catalyst exhibits enhanced suppression of the hydrogen evolution reaction(HER),facilitating proton trans fer and the eCO_(2)R process.Fu rthermore,we explo re the impact of diverse electro n-withdrawing and electron-donating groups coordinated to the macrocycle(R=-F,-H,and-OCH_3)on the electron distribution in the molecular catalysts.Strategic placement of-OCH_3 groups in the macrocycles leads to a favourable oxidation state of the Cu centres and subsequent C-C coupling to form C_(2) products.This research provides fundamental insights into the design and optimization of binuclear Cu molecular catalysts for the electrochemical conversion of CO_(2) to value-added C_(2) products. 展开更多
关键词 Molecular catalyst design selective CO_(2)reduction C_(2)products Density functional theory calculations
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A critical review towards the causes of the iron-based catalysts deactivation mechanisms in the selective oxidation of hydrogen sulfide to elemental sulfur from biogas
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作者 Mostafa Tarek Janaina S.Santos +4 位作者 Victor Márquez Mohammad Fereidooni Mohammad Yazdanpanah Supareak Praserthdam Piyasan Praserthdam 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第3期388-411,I0010,共25页
Hydrogen sulfide(H_(2)S) not only presents significant environmental concerns but also induces severe corrosion in industrial equipment,even at low concentrations.Among various technologies,the selective oxidation of ... Hydrogen sulfide(H_(2)S) not only presents significant environmental concerns but also induces severe corrosion in industrial equipment,even at low concentrations.Among various technologies,the selective oxidation of hydrogen sulfide(SOH_(2)S) to elemental sulfur(S) has emerged as a sustainable and environmentally friendly solution.Due to its unique properties,iron oxide has been extensively investigated as a catalyst for SOH_(2)S;however,rapid deactivation has remained a significant drawback.The causes of iron oxide-based catalysts deactivation mechanisms in SOH_(2)S,including sulfur or sulfate deposition,the transformation of iron species,sintering and excessive oxygen vacancy formation,and active site loss,are thoroughly examined in this review.By focusing on the deactivation mechanisms,this review aims to provide valuable insights into enhancing the stability and efficiency of iron-based catalysts for SOH_(2)S. 展开更多
关键词 selective oxidation of H_(2)S Iron-based Catalysts Mechanism of deactivation Sulfur or sulfate deposition Transformation of iron species Sintering SDG 7
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