A numerical program is built to simulate the performance of a spark ignited two-stroke free-piston engine coupled with a linear generator. The computational model combines a series of dynamic and thermodynamic equatio...A numerical program is built to simulate the performance of a spark ignited two-stroke free-piston engine coupled with a linear generator. The computational model combines a series of dynamic and thermodynamic equations that are solved simultaneously to predict the performances of the engines. The dynamic analysis performed consists of an evaluation of the frictional force and load force introduced by the generator. The thermodynamic analysis used a single zone model to describe the engine' s working cycle which includes intake, scavenging, compression, combustion and expansion, and to evaluate the effect of heat transfer based on the first law of thermodynamics and the ideal gas state equation. Because there is no crankshaft, a time based Wiebe equation was used to express the fraction of fuel burned in the combustion. The calculated results were validated by using the experimental data from another research group. The results indicate that the free-piston generator has some advantages over conventional engines.展开更多
The free-piston engine generator(FPEG)is regarded as the next generation of energy conversion system which may replace traditional engines in the future.The effect of key operational parameters like excess air ratio o...The free-piston engine generator(FPEG)is regarded as the next generation of energy conversion system which may replace traditional engines in the future.The effect of key operational parameters like excess air ratio of input mixture and ignition position on the engine performance of a dual-cylinder FPEG was investigated,and their sensitivity was analyzed in this paper.The operating compression ratio of the system is susceptible to changes in excess air ratio and ignition position.At the same time,it decreases from 15.8 to 6.6 when excess air ratio increases from 0.85 to 1.15,but it increases from 6.1 to 13.3 as ignition position increases from 15 mm to 20 mm.The operating frequency and indicated power are more sensitive to changes in excess air ratio than ignition position.But it is the opposite for the indicated thermal efficiency and friction loss.Excess air ratio and ignition position have a quite similar influence on heat transfer.Therefore,from the perspective of system operation and performance,it is preferable to keep excess air coefficient slightly below 1.0.In contrast,when selecting ignition position,it is of great importance to comprehensively consider the risk of structural damage caused by the increase in the compression ratio and in-cylinder gas pressure.展开更多
A growing global population and the increasing prevalence of diet-related health issues such as“hidden hunger”,obesity,hypertension,and diabetes necessitate a fundamental rethinking of crop design and breeding.Synth...A growing global population and the increasing prevalence of diet-related health issues such as“hidden hunger”,obesity,hypertension,and diabetes necessitate a fundamental rethinking of crop design and breeding.Synthetic metabolic engineering offers a method to modify and redesign metabolic pathways to increase the nutritional value of crops.We summarize recent advances in the biofortification of key nutrients including provitamin A,vitamin C,vitamin B9,iron,zinc,anthocyanins,flavonoids,and unsaturated fatty acids.We discuss the potential of multi-gene stacking,gene editing,enzyme engineering,and artificial intelligence in synthetic metabolic engineering.We propose future research directions and potential solutions centered on leveraging AI-driven systems biology,precision gene editing,enzyme engineering,agrobacterium-mediated genotype-independent transformation,and modular metabolic engineering strategies to develop next-generation nutritionally enhanced super crops and transform global food systems.展开更多
Powder-Fueled Water Ramjet Engine(PFWRE)is the most promising powerplant in underwater high-speed propulsion.However,the effect of powder injection mode on its performance and the mechanism of this effect are not well...Powder-Fueled Water Ramjet Engine(PFWRE)is the most promising powerplant in underwater high-speed propulsion.However,the effect of powder injection mode on its performance and the mechanism of this effect are not well understood.In this paper,a computational framework for multiphase combustion flow is developed and validated.Further,the effects of different injection schemes on flow combustion characteristics and engine performance are evaluated via simulation.Our findings indicate that the dominant recirculation zone in front of the primary water inlet delivers water vapor to the combustor head,providing the necessary oxidant for the ignition and combustion of Al particles.Changing the injection parameters directly affects the flame zone distribution and the ability of the recirculation zone to deliver water vapor,leading to variations in particle ignition delay.The engine combustion efficiency and specific impulse efficiency exhibit a negative correlation with injection height,peaking before declining with increased injection angle.It is shown that particle mixing degree and particle dispersion degree are closely related to engine performance.Enhanced particle mixing in front of the primary water inlet and particle dispersion behind the secondary water inlet are considered favorable approaches to improve engine performance,which promotes the particle combustion process and improves the heat-work conversion efficiency.展开更多
The use of alternative fuels to generate mechanical and thermal energy in engines is a promising and sought-after technological area with its own unique advantages and characteristics.Consequently,enhancing the techni...The use of alternative fuels to generate mechanical and thermal energy in engines is a promising and sought-after technological area with its own unique advantages and characteristics.Consequently,enhancing the technical,economic,and environmental efficiency of gas engines fueled by propane-butane mixture and syngas through optimized operating cycle parameters(including valve timing,ignition timing angle,fuel mixture composition,and compression ratio)is a pressing imperative for scientific and energy sectors.The aim of the study was to investigate and compare the performance of an engine with different compression ratios running on a propane-butane mixture and laboratory syngas.The research’s primary originality lies in its joint study of syngas production technology and the evaluation of the efficiency of a mini power plant fueled by the resulting gas and conventional gas.This article presents a description of the experimental setup,data on measuring instruments,technical characteristics of the mini-power plant,the process for obtaining laboratory syngas,the properties of the gaseous fuels used,and experimental methods.Data on air and fuel consumption,as well as engine efficiency at different compression ratios when running on a propane-butane mixture and syngas,were obtained and analyzed.Converting an engine from a propane-butane mixture to syngas results in a reduction in power of almost 30% and efficiency by 13%–33%.Increasing the compression ratio by 0.9 units causes a rise in maximum efficiency from 0.177 to 0.235 for an engine running on a propane-butane mixture and an increase in maximum efficiency from 0.136 to 0.161 for a syngas engine.It has been confirmed that the compression ratio significantly impacts the technical and economic performance of an engine running on gaseous fuel.The obtained results can be used to modernize existing engines for operation on alternative fuels(syngas)and to design new mini-power plants with promising technical,economic,and environmental characteristics.展开更多
Lacto-N-neotetraose(LNn T)is a crucial neutral core human milk oligosaccharide(HMO).In this study,we established a LNn T-producing Saccharomyces cerevisiae cell factory through comprehensive metabolic engineering.Spec...Lacto-N-neotetraose(LNn T)is a crucial neutral core human milk oligosaccharide(HMO).In this study,we established a LNn T-producing Saccharomyces cerevisiae cell factory through comprehensive metabolic engineering.Specifically,the de novo biosynthetic pathway of LNn T was assembled by heterologously expressing the lactose permease(lac12)from Kluyveromyces lactis and the glycosyltransferase from Neisseria meningitidis in S.cerevisiae.Subsequently,carbon source regulation based on the glucose-sensitive GAL regulatory system was employed to optimize the expression time of heterologous genes,achieving a production of 15.61 mg/L of LNn T in shake-flask fermentation.In addition,the key rate-limiting steps involved in LNn T synthesis pathway were identified and the corresponding genes were overexpressed to enhance LNn T production,resulting in an 8-fold increase in LNn T titer compared to that of parental strain.To our knowledge,this is the first report on LNn T biosynthesis in S.cerevisiae,opening up the possibility of green production of LNn T using food-safe microorganisms.展开更多
Electrocatalytic nitric oxide(NO)reduction reaction(NORR)is a promising and sustainable process that can simultaneously realize green ammonia(NH3)synthesis and hazardous NO removal.However,current NORR performances ar...Electrocatalytic nitric oxide(NO)reduction reaction(NORR)is a promising and sustainable process that can simultaneously realize green ammonia(NH3)synthesis and hazardous NO removal.However,current NORR performances are far from practical needs due to the lack of efficient electrocatalysts.Engineering the lattice of metal-based nanomaterials via phase control has emerged as an effective strategy to modulate their intrinsic electrocatalytic properties.Herein,we realize boron(B)-insertion-induced phase regulation of rhodium(Rh)nanocrystals to obtain amorphous Rh_(4)B nanoparticles(NPs)and hexagonal close-packed(hcp)RhB NPs through a facile wet-chemical method.A high Faradaic efficiency(92.1±1.2%)and NH_(3) yield rate(629.5±11.0μmol h^(−1) cm^(−2))are achieved over hcp RhB NPs,far superior to those of most reported NORR nanocatalysts.In situ spectro-electrochemical analysis and density functional theory simulations reveal that the excellent electrocatalytic performances of hcp RhB NPs are attributed to the upshift of d-band center,enhanced NO adsorption/activation profile,and greatly reduced energy barrier of the rate-determining step.A demonstrative Zn-NO battery is assembled using hcp RhB NPs as the cathode and delivers a peak power density of 4.33 mW cm−2,realizing simultaneous NO removal,NH3 synthesis,and electricity output.展开更多
Tumor immunotherapy has been recognized by Science as the most promising therapeutic approach for tumor eradication,with engineered bacteria emerging as a particularly promising modality.As a novel drug delivery platf...Tumor immunotherapy has been recognized by Science as the most promising therapeutic approach for tumor eradication,with engineered bacteria emerging as a particularly promising modality.As a novel drug delivery platform,the engineered bacterial therapeutics demonstrate exceptional targeting precision and favorable safety profiles.Through attenuation and programmable control strategies,these systems enable highly specific drug delivery,showing significant therapeutic potential in oncology and inflammatory bowel disease(IBD).展开更多
With the advent of the AI era,how can students effectively utilize generative AI large models to assist in course learning?At the same time,how can teachers utilize generative AI tools and the teaching concept of OBE ...With the advent of the AI era,how can students effectively utilize generative AI large models to assist in course learning?At the same time,how can teachers utilize generative AI tools and the teaching concept of OBE to stimulate students’innovative consciousness and teamwork ability,enabling students to identify some problems in a certain industry or field and creatively propose feasible solutions,and truly achieve the cultivation of new models in software engineering course teaching with the assistance of generative AI tools?This paper presents research and practice on a new model for cultivating software engineering courses that integrates generative AI and OBE,introduces the specific process of teaching reform and practice,and finally explains the achievements of teaching reform.展开更多
Photocatalytic transfer hydrogenation using water as the proton source has emerged as an attractive and green approach for the catalytic reduction of unsaturated bonds.Herein,we report an oxygen-defective TiO_(2)-supp...Photocatalytic transfer hydrogenation using water as the proton source has emerged as an attractive and green approach for the catalytic reduction of unsaturated bonds.Herein,we report an oxygen-defective TiO_(2)-supported palladium catalyst(Pd-TiO_(2)-Ov)for efficient photocatalytic water-donating transfer hydrogenation of anethole towards 4-n-propylanisole in a high yield of 99.9%,which is significantly higher compared to the pristine TiO_(2)-supported palladium catalyst(Pd-TiO_(2),74%).The enhanced performance is ascribed to the presence of oxygen vacancies,which facilitate light absorption and suppress the recombination of photogenerated electron-hole pairs.Furthermore,the Pd-TiO_(2)-Ov is versatile in hydrogenating various alkene substrates including those with hydroxyl,ether,fluoride,and chloride functional groups in full conversion,thus offering a green method for transfer hydrogenation of alkenes.This study provides new insights and advances in current hydrogenation technology with water as the proton source.展开更多
All-inorganic lead-free perovskite solar cells have emerged as environmentally benign candidates;however,their device performance is still constrained by pronounced carrier recombination losses in the bulk and at inte...All-inorganic lead-free perovskite solar cells have emerged as environmentally benign candidates;however,their device performance is still constrained by pronounced carrier recombination losses in the bulk and at interfaces.By combining energy band alignment analysis with detailed modeling of recombination mechanisms,a systematic strategy for optimizing hole transport layers is developed.The results reveal that a negative valence band offset produces a cliff-like interface,which facilitates hole extraction while also accounting for the observed variations in open-circuit voltage.Furthermore,short-circuit current losses are quantitatively attributed to different recombination pathways,modeled by incorporating radiative,Shockley–Read–Hall,Auger,and interface recombination processes.This comprehensive approach not only clarifies the correlation between energy level alignment and recombination dynamics but also highlights the competing roles of band offset and interface defects in determining device performance.The optimized device architecture,based on Ge-based lead-free perovskites,achieves a power conversion efficiency of 25.1%,with an open-circuit voltage of 1.29 V,a short-circuit current density of 22.5 mA·cm^(-2),and a fill factor of 86.3%.These findings provide theoretical guidance for designing stable,high-performance,and environmentally friendly lead-free perovskite solar cells.展开更多
High-performance alloys are indispensable in modern engineering because of their exceptional strength,ductility,corrosion resistance,fatigue resistance,and thermal stability,which are all significantly influenced by t...High-performance alloys are indispensable in modern engineering because of their exceptional strength,ductility,corrosion resistance,fatigue resistance,and thermal stability,which are all significantly influenced by the alloy interface structures.Despite substantial efforts,a comprehensive overview of interface engineering of high-performance alloys has not been presented so far.In this study,the interfaces in high-performance alloys,particularly grain and phase boundaries,were systematically examined,with emphasis on their crystallographic characteristics and chemical element segregations.The effects of the interfaces on the electrical conductivity,mechanical strength,toughness,hydrogen embrittlement resistance,and thermal stability of the alloys were elucidated.Moreover,correlations among various types of interfaces and advanced experimental and computational techniques were examined using big data analytics,enabling robust design strategies.Challenges currently faced in the field of interface engineering and emerging opportunities in the field are also discussed.The study results would guide the development of next-generation high-performance alloys.展开更多
Methanol is a very promising clean alternative fuel with low carbon content and high octane number,and this makes it well suited to the free-piston engine generator(FPEG)with variable compression ratio characteristics...Methanol is a very promising clean alternative fuel with low carbon content and high octane number,and this makes it well suited to the free-piston engine generator(FPEG)with variable compression ratio characteristics.To the authors’knowledge there are no relevant studies on the application of methanol for FPEG in recent literatures.In this paper,the effects of methanol substitution ratios(MSR)and load ratios on the performances and combustion characteristics of a methane/methanol dual-fuel FPEG have been investigated experimentally and numerically.The results show that the under the gas-liquid two-phase combustion startup strategy,the methane/methanol dual-fuel FPEG can be successfully started and achieve steady operation.Due to higher laminar flame speed(LFS)and the oxygen content of methanol resulting in a faster burning rate,the peak pressure increases by 43.9%from 1.344 MPa for pure methane to 1.934 MPa for 15%of MSR and the corresponding cycle-to-cycle variation decreases from 3.36 to 1.62.The FPEG operating frequency and indicated power gradually increase with the increase of the MSR.Both of them reach maximum values of 34.6 Hz and 193 W at 15%of MSR,which are increased by 19.3%and 49.6%in comparison with the pure methane.However,under specific MSR,both of them decrease with the load ratio increasing because of the large electromagnetic resistance force from the linear generator.CO and CH emissions decrease with the increase of MSR because methanol addition promotes complete combustion of mixture.NOx emissions gradually decrease with MSR increasing owing to the low combustion temperature resulting from the high latent heat of methanol evaporation.The numerical results show that with the increase of MSR,the methane/methanol mixture presents faster flame propagation speed and higher combustion efficiency;while the ignition delay as well as CA10,CA50 and CA90 is significantly shortened due to the increase of active radicals such as H,OH,O and H_(2)O_(2).展开更多
Aqueous zinc(Zn)metal batteries(AZMBs)have distinct advantages in terms of safety and cost-effectiveness.However,the industrial application of AZMBs is currently not ready due to challenges of Zn dendrite growth and t...Aqueous zinc(Zn)metal batteries(AZMBs)have distinct advantages in terms of safety and cost-effectiveness.However,the industrial application of AZMBs is currently not ready due to challenges of Zn dendrite growth and the side reactions such as hydrogen evolution reaction(HER)on the Zn anodes.In this review,we discuss how inorganic interfaces impact the Zn^(2+)plating/stripping reaction and overall cell performance.The discussion is categorized based on the types of inorganic materials,including metal oxides,other metal compounds,and inorganic salts.The proposed protection mechanisms for Zn metal anodes are highlighted,with a focus on the dendrite and HER inhibition mechanisms facilitated by various inorganic materials.We also provide our perspective on the rational design of advanced interfaces to enable highly reversible Zn^(2+)plating/stripping reactions toward highly stable AZMBs,paving the way for their practical implementation in energy storage.展开更多
Despite demonstrating significant anti-tumor potential as an artemisinin derivative,artesunate faces delivery efficiency challenges due to low water solubility and insufficient targeting specificity.To improve the del...Despite demonstrating significant anti-tumor potential as an artemisinin derivative,artesunate faces delivery efficiency challenges due to low water solubility and insufficient targeting specificity.To improve the delivery efficiency,we engineered three artesunate(ART) derivatives,AC_(15)-L(linear),AC_(15)-B(branched),and AC_(15)-C(cyclic) with distinct aliphatic chain architectures.Unexpectedly,we observed that AC_(15)-C exhibited superior cytotoxicity against 4T1 breast cancer cells,and had the highest binding affinity for Lon protease 1(LONP1)(-72.6 kcal/mol).Subsequently,disulfide bond-containing lipid-PEG(DSPESS-PEG2K) modified chain architecture-engineered ART derivatives nanoassemblies(NAs) were developed to mitigate solubility-related limitations while enhancing targeting precision.Molecular docking and experimental validation demonstrated that ART derivatives inhibited LONP1 through hydrophobic interactions while preserved Fe^(2+)-mediated Fenton-like reaction activity.In vitro and in vivo evaluations demonstrated that AC_(15)-C NAs outperformed free ART and other NAs,suppressing 4T1 tumor growth via dual action:LONP1-directed mitochondrial proteostasis collapse and reactive oxygen species(ROS) amplification through Fe^(2+)-ART interactions.This study elucidated a novel anti-tumor mechanism of ART through the rational design of derivatives with spatially configured aliphatic chains,and developed reductionresponsive NAs to provide an advanced delivery strategy.展开更多
Radiative cooling systems(RCSs)possess the distinctive capability to dissipate heat energy via solar and thermal radiation,making them suitable for thermal regulation and energy conservation applications,essential for...Radiative cooling systems(RCSs)possess the distinctive capability to dissipate heat energy via solar and thermal radiation,making them suitable for thermal regulation and energy conservation applications,essential for mitigating the energy crisis.A comprehensive review connecting the advancements in engineered radiative cooling systems(ERCSs),encompassing material and structural design as well as thermal and energy-related applications,is currently absent.Herein,this review begins with a concise summary of the essential concepts of ERCSs,followed by an introduction to engineered materials and structures,containing nature-inspired designs,chromatic materials,meta-structural configurations,and multilayered constructions.It subsequently encapsulates the primary applications,including thermal-regulating textiles and energy-saving devices.Next,it highlights the challenges of ERCSs,including maximized thermoregulatory effects,environmental adaptability,scalability and sustainability,and interdisciplinary integration.It seeks to offer direction for forthcoming fundamental research and industrial advancement of radiative cooling systems in real-world applications.展开更多
文摘A numerical program is built to simulate the performance of a spark ignited two-stroke free-piston engine coupled with a linear generator. The computational model combines a series of dynamic and thermodynamic equations that are solved simultaneously to predict the performances of the engines. The dynamic analysis performed consists of an evaluation of the frictional force and load force introduced by the generator. The thermodynamic analysis used a single zone model to describe the engine' s working cycle which includes intake, scavenging, compression, combustion and expansion, and to evaluate the effect of heat transfer based on the first law of thermodynamics and the ideal gas state equation. Because there is no crankshaft, a time based Wiebe equation was used to express the fraction of fuel burned in the combustion. The calculated results were validated by using the experimental data from another research group. The results indicate that the free-piston generator has some advantages over conventional engines.
基金Projects(51675043,52005038)supported by the National Natural Science Foundation of China。
文摘The free-piston engine generator(FPEG)is regarded as the next generation of energy conversion system which may replace traditional engines in the future.The effect of key operational parameters like excess air ratio of input mixture and ignition position on the engine performance of a dual-cylinder FPEG was investigated,and their sensitivity was analyzed in this paper.The operating compression ratio of the system is susceptible to changes in excess air ratio and ignition position.At the same time,it decreases from 15.8 to 6.6 when excess air ratio increases from 0.85 to 1.15,but it increases from 6.1 to 13.3 as ignition position increases from 15 mm to 20 mm.The operating frequency and indicated power are more sensitive to changes in excess air ratio than ignition position.But it is the opposite for the indicated thermal efficiency and friction loss.Excess air ratio and ignition position have a quite similar influence on heat transfer.Therefore,from the perspective of system operation and performance,it is preferable to keep excess air coefficient slightly below 1.0.In contrast,when selecting ignition position,it is of great importance to comprehensively consider the risk of structural damage caused by the increase in the compression ratio and in-cylinder gas pressure.
基金supported by grants from the Guangxi Science and Technology Major Project(GKAA24206023)the Biological Breeding-National Science and Technology Major Project(2024ZD04077)+2 种基金the National Natural Science Foundation of China(32272120)the National Key Research and Development Program of China(2024YFF1000800)the Guangdong Basic Research Center of Excellence for Precise Breeding of Future Crops Major Project(FCBRCE-202502,FCBRCE-202504).
文摘A growing global population and the increasing prevalence of diet-related health issues such as“hidden hunger”,obesity,hypertension,and diabetes necessitate a fundamental rethinking of crop design and breeding.Synthetic metabolic engineering offers a method to modify and redesign metabolic pathways to increase the nutritional value of crops.We summarize recent advances in the biofortification of key nutrients including provitamin A,vitamin C,vitamin B9,iron,zinc,anthocyanins,flavonoids,and unsaturated fatty acids.We discuss the potential of multi-gene stacking,gene editing,enzyme engineering,and artificial intelligence in synthetic metabolic engineering.We propose future research directions and potential solutions centered on leveraging AI-driven systems biology,precision gene editing,enzyme engineering,agrobacterium-mediated genotype-independent transformation,and modular metabolic engineering strategies to develop next-generation nutritionally enhanced super crops and transform global food systems.
基金supported by the National Natural Science Foundation of China(No.22305053)the Fundamental Research Funds for the Central Universities,China(No.3072024WD0201)。
文摘Powder-Fueled Water Ramjet Engine(PFWRE)is the most promising powerplant in underwater high-speed propulsion.However,the effect of powder injection mode on its performance and the mechanism of this effect are not well understood.In this paper,a computational framework for multiphase combustion flow is developed and validated.Further,the effects of different injection schemes on flow combustion characteristics and engine performance are evaluated via simulation.Our findings indicate that the dominant recirculation zone in front of the primary water inlet delivers water vapor to the combustor head,providing the necessary oxidant for the ignition and combustion of Al particles.Changing the injection parameters directly affects the flame zone distribution and the ability of the recirculation zone to deliver water vapor,leading to variations in particle ignition delay.The engine combustion efficiency and specific impulse efficiency exhibit a negative correlation with injection height,peaking before declining with increased injection angle.It is shown that particle mixing degree and particle dispersion degree are closely related to engine performance.Enhanced particle mixing in front of the primary water inlet and particle dispersion behind the secondary water inlet are considered favorable approaches to improve engine performance,which promotes the particle combustion process and improves the heat-work conversion efficiency.
文摘The use of alternative fuels to generate mechanical and thermal energy in engines is a promising and sought-after technological area with its own unique advantages and characteristics.Consequently,enhancing the technical,economic,and environmental efficiency of gas engines fueled by propane-butane mixture and syngas through optimized operating cycle parameters(including valve timing,ignition timing angle,fuel mixture composition,and compression ratio)is a pressing imperative for scientific and energy sectors.The aim of the study was to investigate and compare the performance of an engine with different compression ratios running on a propane-butane mixture and laboratory syngas.The research’s primary originality lies in its joint study of syngas production technology and the evaluation of the efficiency of a mini power plant fueled by the resulting gas and conventional gas.This article presents a description of the experimental setup,data on measuring instruments,technical characteristics of the mini-power plant,the process for obtaining laboratory syngas,the properties of the gaseous fuels used,and experimental methods.Data on air and fuel consumption,as well as engine efficiency at different compression ratios when running on a propane-butane mixture and syngas,were obtained and analyzed.Converting an engine from a propane-butane mixture to syngas results in a reduction in power of almost 30% and efficiency by 13%–33%.Increasing the compression ratio by 0.9 units causes a rise in maximum efficiency from 0.177 to 0.235 for an engine running on a propane-butane mixture and an increase in maximum efficiency from 0.136 to 0.161 for a syngas engine.It has been confirmed that the compression ratio significantly impacts the technical and economic performance of an engine running on gaseous fuel.The obtained results can be used to modernize existing engines for operation on alternative fuels(syngas)and to design new mini-power plants with promising technical,economic,and environmental characteristics.
基金funded by the National Key Research and Development Program of China(2022YFF1100300)National Natural Science Foundation of China(22108097)+2 种基金Key Research and Development Program of Jiangsu Province(BE2022850)Taihu Innovation-Leading Talent of Wuxi City(1026010241230040)Cross-Integration Innovation Funding of SFST(SFST2023-KY-10).
文摘Lacto-N-neotetraose(LNn T)is a crucial neutral core human milk oligosaccharide(HMO).In this study,we established a LNn T-producing Saccharomyces cerevisiae cell factory through comprehensive metabolic engineering.Specifically,the de novo biosynthetic pathway of LNn T was assembled by heterologously expressing the lactose permease(lac12)from Kluyveromyces lactis and the glycosyltransferase from Neisseria meningitidis in S.cerevisiae.Subsequently,carbon source regulation based on the glucose-sensitive GAL regulatory system was employed to optimize the expression time of heterologous genes,achieving a production of 15.61 mg/L of LNn T in shake-flask fermentation.In addition,the key rate-limiting steps involved in LNn T synthesis pathway were identified and the corresponding genes were overexpressed to enhance LNn T production,resulting in an 8-fold increase in LNn T titer compared to that of parental strain.To our knowledge,this is the first report on LNn T biosynthesis in S.cerevisiae,opening up the possibility of green production of LNn T using food-safe microorganisms.
基金funding support from General Research Fund[Project No.14300525]from the Research Grants Council(RGC)of Hong Kong SAR,Chinafunding support from Natural Science Foundation of China(NSFC)Young Scientists Fund(Project No.22305203)+2 种基金NSFC Projects Nos.22309123,22422303,22303011,22033002,92261112 and U21A20328support from the Hong Kong Branch of National Precious Metals Material Engineering Research Center(NPMM)at City University of Hong Kongsupport from Young Collaborative Research Grant[Project No.C1003-23Y]support from RGC of Hong Kong SAR,China.
文摘Electrocatalytic nitric oxide(NO)reduction reaction(NORR)is a promising and sustainable process that can simultaneously realize green ammonia(NH3)synthesis and hazardous NO removal.However,current NORR performances are far from practical needs due to the lack of efficient electrocatalysts.Engineering the lattice of metal-based nanomaterials via phase control has emerged as an effective strategy to modulate their intrinsic electrocatalytic properties.Herein,we realize boron(B)-insertion-induced phase regulation of rhodium(Rh)nanocrystals to obtain amorphous Rh_(4)B nanoparticles(NPs)and hexagonal close-packed(hcp)RhB NPs through a facile wet-chemical method.A high Faradaic efficiency(92.1±1.2%)and NH_(3) yield rate(629.5±11.0μmol h^(−1) cm^(−2))are achieved over hcp RhB NPs,far superior to those of most reported NORR nanocatalysts.In situ spectro-electrochemical analysis and density functional theory simulations reveal that the excellent electrocatalytic performances of hcp RhB NPs are attributed to the upshift of d-band center,enhanced NO adsorption/activation profile,and greatly reduced energy barrier of the rate-determining step.A demonstrative Zn-NO battery is assembled using hcp RhB NPs as the cathode and delivers a peak power density of 4.33 mW cm−2,realizing simultaneous NO removal,NH3 synthesis,and electricity output.
基金supported by the Hunan Natural Science Foundation(2023JJ20022).
文摘Tumor immunotherapy has been recognized by Science as the most promising therapeutic approach for tumor eradication,with engineered bacteria emerging as a particularly promising modality.As a novel drug delivery platform,the engineered bacterial therapeutics demonstrate exceptional targeting precision and favorable safety profiles.Through attenuation and programmable control strategies,these systems enable highly specific drug delivery,showing significant therapeutic potential in oncology and inflammatory bowel disease(IBD).
基金supported by the Shanghai Municipal Education Research Project“Exploring the Practical Application of Generative Artificial Intelligence in Cultivating Innovative Thinking and Capabilities of Interdisciplinary Application Technology Talents‘Practice Path’”(C2025299)the university-level postgraduate course project“Software Process Management”(PX-2025251502)of Shanghai Sanda Universitythe key course project at the university level of Shanghai Sanda University,“Introduction to Software Engineering”(PX-5241216).
文摘With the advent of the AI era,how can students effectively utilize generative AI large models to assist in course learning?At the same time,how can teachers utilize generative AI tools and the teaching concept of OBE to stimulate students’innovative consciousness and teamwork ability,enabling students to identify some problems in a certain industry or field and creatively propose feasible solutions,and truly achieve the cultivation of new models in software engineering course teaching with the assistance of generative AI tools?This paper presents research and practice on a new model for cultivating software engineering courses that integrates generative AI and OBE,introduces the specific process of teaching reform and practice,and finally explains the achievements of teaching reform.
基金supported by the National Key Research and Development Program of China(2023YFD2200505)National Natural Science Foundation of China(22202105),Natural Science Foundation of Jiangsu Higher Education Institutions of China(21KJA150003)the Innovation and Entrepreneurship Team Program of Jiangsu Province(JSSCTD202345).
文摘Photocatalytic transfer hydrogenation using water as the proton source has emerged as an attractive and green approach for the catalytic reduction of unsaturated bonds.Herein,we report an oxygen-defective TiO_(2)-supported palladium catalyst(Pd-TiO_(2)-Ov)for efficient photocatalytic water-donating transfer hydrogenation of anethole towards 4-n-propylanisole in a high yield of 99.9%,which is significantly higher compared to the pristine TiO_(2)-supported palladium catalyst(Pd-TiO_(2),74%).The enhanced performance is ascribed to the presence of oxygen vacancies,which facilitate light absorption and suppress the recombination of photogenerated electron-hole pairs.Furthermore,the Pd-TiO_(2)-Ov is versatile in hydrogenating various alkene substrates including those with hydroxyl,ether,fluoride,and chloride functional groups in full conversion,thus offering a green method for transfer hydrogenation of alkenes.This study provides new insights and advances in current hydrogenation technology with water as the proton source.
基金supported by the National Natural Science Foundation of China(Grant Nos.52102165 and 62474056)the Natural Science Foundation of Nanjing University of Posts and Telecommunications(Grant Nos.NY221029 and NY222165)。
文摘All-inorganic lead-free perovskite solar cells have emerged as environmentally benign candidates;however,their device performance is still constrained by pronounced carrier recombination losses in the bulk and at interfaces.By combining energy band alignment analysis with detailed modeling of recombination mechanisms,a systematic strategy for optimizing hole transport layers is developed.The results reveal that a negative valence band offset produces a cliff-like interface,which facilitates hole extraction while also accounting for the observed variations in open-circuit voltage.Furthermore,short-circuit current losses are quantitatively attributed to different recombination pathways,modeled by incorporating radiative,Shockley–Read–Hall,Auger,and interface recombination processes.This comprehensive approach not only clarifies the correlation between energy level alignment and recombination dynamics but also highlights the competing roles of band offset and interface defects in determining device performance.The optimized device architecture,based on Ge-based lead-free perovskites,achieves a power conversion efficiency of 25.1%,with an open-circuit voltage of 1.29 V,a short-circuit current density of 22.5 mA·cm^(-2),and a fill factor of 86.3%.These findings provide theoretical guidance for designing stable,high-performance,and environmentally friendly lead-free perovskite solar cells.
基金supported by the National Natural Science Foundation of China(Nos.52122408 and 52474397)the High-level Talent Research Start-up Project Funding of Henan Academy of Sciences(No.242017127)+1 种基金the financial support from the Fundamental Research Funds for the Central Universities(University of Science and Technology Beijing(USTB),Nos.FRF-TP-2021-04C1 and 06500135)supported by USTB MatCom of Beijing Advanced Innovation Center for Materials Genome Engineering。
文摘High-performance alloys are indispensable in modern engineering because of their exceptional strength,ductility,corrosion resistance,fatigue resistance,and thermal stability,which are all significantly influenced by the alloy interface structures.Despite substantial efforts,a comprehensive overview of interface engineering of high-performance alloys has not been presented so far.In this study,the interfaces in high-performance alloys,particularly grain and phase boundaries,were systematically examined,with emphasis on their crystallographic characteristics and chemical element segregations.The effects of the interfaces on the electrical conductivity,mechanical strength,toughness,hydrogen embrittlement resistance,and thermal stability of the alloys were elucidated.Moreover,correlations among various types of interfaces and advanced experimental and computational techniques were examined using big data analytics,enabling robust design strategies.Challenges currently faced in the field of interface engineering and emerging opportunities in the field are also discussed.The study results would guide the development of next-generation high-performance alloys.
基金supported by the Space Application System of China Manned Space Program.
文摘Methanol is a very promising clean alternative fuel with low carbon content and high octane number,and this makes it well suited to the free-piston engine generator(FPEG)with variable compression ratio characteristics.To the authors’knowledge there are no relevant studies on the application of methanol for FPEG in recent literatures.In this paper,the effects of methanol substitution ratios(MSR)and load ratios on the performances and combustion characteristics of a methane/methanol dual-fuel FPEG have been investigated experimentally and numerically.The results show that the under the gas-liquid two-phase combustion startup strategy,the methane/methanol dual-fuel FPEG can be successfully started and achieve steady operation.Due to higher laminar flame speed(LFS)and the oxygen content of methanol resulting in a faster burning rate,the peak pressure increases by 43.9%from 1.344 MPa for pure methane to 1.934 MPa for 15%of MSR and the corresponding cycle-to-cycle variation decreases from 3.36 to 1.62.The FPEG operating frequency and indicated power gradually increase with the increase of the MSR.Both of them reach maximum values of 34.6 Hz and 193 W at 15%of MSR,which are increased by 19.3%and 49.6%in comparison with the pure methane.However,under specific MSR,both of them decrease with the load ratio increasing because of the large electromagnetic resistance force from the linear generator.CO and CH emissions decrease with the increase of MSR because methanol addition promotes complete combustion of mixture.NOx emissions gradually decrease with MSR increasing owing to the low combustion temperature resulting from the high latent heat of methanol evaporation.The numerical results show that with the increase of MSR,the methane/methanol mixture presents faster flame propagation speed and higher combustion efficiency;while the ignition delay as well as CA10,CA50 and CA90 is significantly shortened due to the increase of active radicals such as H,OH,O and H_(2)O_(2).
基金supported by the National Natural Science Foundation of China(52272183)the Fundamental Research Funds for the Central Universities(buctrc202316)the support of the China Experience Fund and the Stephen Slavens Faculty Scholar Endowment Fund from Oregon State University。
文摘Aqueous zinc(Zn)metal batteries(AZMBs)have distinct advantages in terms of safety and cost-effectiveness.However,the industrial application of AZMBs is currently not ready due to challenges of Zn dendrite growth and the side reactions such as hydrogen evolution reaction(HER)on the Zn anodes.In this review,we discuss how inorganic interfaces impact the Zn^(2+)plating/stripping reaction and overall cell performance.The discussion is categorized based on the types of inorganic materials,including metal oxides,other metal compounds,and inorganic salts.The proposed protection mechanisms for Zn metal anodes are highlighted,with a focus on the dendrite and HER inhibition mechanisms facilitated by various inorganic materials.We also provide our perspective on the rational design of advanced interfaces to enable highly reversible Zn^(2+)plating/stripping reactions toward highly stable AZMBs,paving the way for their practical implementation in energy storage.
基金financially supported by the Liaoning Revitalization Talents Program (No.XLYC2403107)the Excellent Youth Science Foundation of Liaoning Province (No.2024JH3/10200046)the Basic Scientific Research Project of Liaoning Provincial Department of Education (No.LJ212410163015)。
文摘Despite demonstrating significant anti-tumor potential as an artemisinin derivative,artesunate faces delivery efficiency challenges due to low water solubility and insufficient targeting specificity.To improve the delivery efficiency,we engineered three artesunate(ART) derivatives,AC_(15)-L(linear),AC_(15)-B(branched),and AC_(15)-C(cyclic) with distinct aliphatic chain architectures.Unexpectedly,we observed that AC_(15)-C exhibited superior cytotoxicity against 4T1 breast cancer cells,and had the highest binding affinity for Lon protease 1(LONP1)(-72.6 kcal/mol).Subsequently,disulfide bond-containing lipid-PEG(DSPESS-PEG2K) modified chain architecture-engineered ART derivatives nanoassemblies(NAs) were developed to mitigate solubility-related limitations while enhancing targeting precision.Molecular docking and experimental validation demonstrated that ART derivatives inhibited LONP1 through hydrophobic interactions while preserved Fe^(2+)-mediated Fenton-like reaction activity.In vitro and in vivo evaluations demonstrated that AC_(15)-C NAs outperformed free ART and other NAs,suppressing 4T1 tumor growth via dual action:LONP1-directed mitochondrial proteostasis collapse and reactive oxygen species(ROS) amplification through Fe^(2+)-ART interactions.This study elucidated a novel anti-tumor mechanism of ART through the rational design of derivatives with spatially configured aliphatic chains,and developed reductionresponsive NAs to provide an advanced delivery strategy.
基金support from the Contract Research(“Development of Breathable Fabrics with Nano-Electrospun Membrane”,CityU ref.:9231419“Research and application of antibacterial and healing-promoting smart nanofiber dressing for children’s burn wounds”,CityU ref:PJ9240111)+1 种基金the National Natural Science Foundation of China(“Study of Multi-Responsive Shape Memory Polyurethane Nanocomposites Inspired by Natural Fibers”,Grant No.51673162)Startup Grant of CityU(“Laboratory of Wearable Materials for Healthcare”,Grant No.9380116).
文摘Radiative cooling systems(RCSs)possess the distinctive capability to dissipate heat energy via solar and thermal radiation,making them suitable for thermal regulation and energy conservation applications,essential for mitigating the energy crisis.A comprehensive review connecting the advancements in engineered radiative cooling systems(ERCSs),encompassing material and structural design as well as thermal and energy-related applications,is currently absent.Herein,this review begins with a concise summary of the essential concepts of ERCSs,followed by an introduction to engineered materials and structures,containing nature-inspired designs,chromatic materials,meta-structural configurations,and multilayered constructions.It subsequently encapsulates the primary applications,including thermal-regulating textiles and energy-saving devices.Next,it highlights the challenges of ERCSs,including maximized thermoregulatory effects,environmental adaptability,scalability and sustainability,and interdisciplinary integration.It seeks to offer direction for forthcoming fundamental research and industrial advancement of radiative cooling systems in real-world applications.