As a newly developed precision technology, casting-forging complex near net forming process is utilized to produce complex components with a short lead time, low cost and high precision, thus to accelerate the respons...As a newly developed precision technology, casting-forging complex near net forming process is utilized to produce complex components with a short lead time, low cost and high precision, thus to accelerate the response speed of the market and enhance the competitive power of products. In this paper, the casting-forging complex near net forming process of alternator claw pole was developed and investigated with a combination of experimental and numerical simulation method. Qualified near net workpiece was manufactured, mechanical parameter and relative field information during the forming process was also obtained. While the alternator claw-pole is processed with this technology, the forming force is small, the process is short and the quality of forgings is perfect. Therefore, the complex casting-forging near net forming process of claw-pole is an energy and material saving technology, which will have a vast developing and application prospect in the future.展开更多
To solve the low efficiency of electric excitation claw-pole synchronous generator（EECPSG） and regulate the magnetic field of permanent magnet （PM） claw-pole synchronous generator（PMCPSG）, a novel hybrid excitat...To solve the low efficiency of electric excitation claw-pole synchronous generator（EECPSG） and regulate the magnetic field of permanent magnet （PM） claw-pole synchronous generator（PMCPSG）, a novel hybrid excitation claw-pole synchronous generator （HECPSG）with magnetic circuit series connection is proposed. Through the simulation study on the generator using the calculation method for magnetic circuit and 3-D finite element method （FEA）, the appropriate magnet thickness and the number of pole-pairs for the proposed generator are determined. Its off-loading characteristics, load characteristics, and regulation behaviors are investigated. The study shows that the appropriate number of pole-pairs in HECPSG with series magnetic circuits is two, and there exists an optimum magnet thickness. Compared to EECPSG, HECPSG realizes dual-directional control to the excitation current. Moreover, the generator can adjust the output voltage and keep the output voltage stable in a broad load range. Under the condition of same parametes, the motor has higer air-gap flux density and power density.展开更多
The casting-forging combined technique and the closed die forging without flash-less are both new developed material working methods. The former can not only decrease forming operations of forgings, but also increase ...The casting-forging combined technique and the closed die forging without flash-less are both new developed material working methods. The former can not only decrease forming operations of forgings, but also increase the material utilization ratio. Therefore, it is applied to produce more complex forgings. The latter is required for forging precise parts without burrs. The alternator pole is a complex forging, which was usually produced by hot forging, upsetting-extrusion or upsetting-extrusion and bending processes. During these processes, not only the forming force is higher, but the material of burrs accounts for 30 percent or so of total required material. And burrs are difficult to remove in the sequential machining process. In accordance with defects exiting in current manufacturing of alternator poles by upsetting-extruding process, such as more material demand, higher forming force and difficulty of next machining, a casting-forging precision process of alternator poles was developed and investigated in this paper. In the process, the pole was formed by two operations. One is the pre-forming operation by casting. The other is the final forming operation by the closed precision forging process. This can not only shorten processes, decrease material and power demand, but also increase precision of forgings. First, the casting blocker was designed considering the casting process and the forging ratio and the mode of deformation. Then the die structure for closed precision forging was designed, and the closing device for forging dies with spring assemblies in order to provide the necessary closing force was also designed. Finally the forming processes was investigated by test and numerical simulation method to optimum process parameters and die structure design parameters. The result can provide basis for applying the process to manufacture poles in practice.展开更多
Based on the structure analysis of alternator poles, two closed die forging steps in one heat forming process of alternator poles were put forward, as well as the forming die system. Firstly, a thicker bottom base of ...Based on the structure analysis of alternator poles, two closed die forging steps in one heat forming process of alternator poles were put forward, as well as the forming die system. Firstly, a thicker bottom base of alternator poles was per-formed by radial forging, then the middle boss and pole claw were forming on the bottom base by backward extrusion. A 3-D coupled thermo-mechanical finite element model was created. The billet deformation, metal flow and forming load were obtained. The results showed that a filling well forging without overlap defects could be obtained by this process, and that?the forming load at the first step increased slowly, but the load increased sharply at the second step when the middle boss was filling completely by the former process. An improved process was put forward, which changed the flow mode in the second forging step, it can considerably reduce the final forging load.展开更多
We proposed the flat-type permanent magnet linear alternator (LA) for free piston linear alternators (FPLAs) instead of the tubular one. Using the finite element method (FEM), we compare these two kinds of LAs. The FE...We proposed the flat-type permanent magnet linear alternator (LA) for free piston linear alternators (FPLAs) instead of the tubular one. Using the finite element method (FEM), we compare these two kinds of LAs. The FEM result shows that the flat-type permanent magnet LA has higher efficiency and larger output specific power than the tubular one, therefore more suitable for FPLAs, and that the alternator design can be optimized with respect to the permanent magnet length as well as the air gap.展开更多
Demagnetization behavior of Halbach magnetized compensated pulsed alternator(CPA)is studied by using finite element method(FEM)under the different demagnetization factors in this paper.The effect of armature reaction ...Demagnetization behavior of Halbach magnetized compensated pulsed alternator(CPA)is studied by using finite element method(FEM)under the different demagnetization factors in this paper.The effect of armature reaction magnetic field and thermal rise on demagnetization of PMs is analyzed.This paper investigates the effect of different demagnetization factors on magnetic field distribution,load current,and no-load phase voltage.A series of dynamic demagnetization points in Halbach array permanent magnet(PM)are evaluated to search the worst working point.Partial demagnetization risk can be represented by the worst working point,and the global demagnetization of the PM is represented by the no-load phase voltage characteristics after discharge.The research results demonstrated that the compensation shield with a certain thickness can increase the discharge current and weaken the demagnetization influence of armature reaction.The demagnetization effect of armature reaction on PMs at high temperatures will be strengthened.展开更多
Single-pixel imaging(SPI)enables efficient sensing in challenging conditions.However,the requirement for numerous samplings constrains its practicality.We address the challenge of high-quality SPI reconstruction at ul...Single-pixel imaging(SPI)enables efficient sensing in challenging conditions.However,the requirement for numerous samplings constrains its practicality.We address the challenge of high-quality SPI reconstruction at ultra-low sampling rates.We develop an alternative optimization with physics and a data-driven diffusion network(APD-Net).It features alternative optimization driven by the learned task-agnostic natural image prior and the task-specific physics prior.During the training stage,APD-Net harnesses the power of diffusion models to capture data-driven statistics of natural signals.In the inference stage,the physics prior is introduced as corrective guidance to ensure consistency between the physics imaging model and the natural image probability distribution.Through alternative optimization,APD-Net reconstructs data-efficient,high-fidelity images that are statistically and physically compliant.To accelerate reconstruction,initializing images with the inverse SPI physical model reduces the need for reconstruction inference from 100 to 30 steps.Through both numerical simulations and real prototype experiments,APD-Net achieves high-quality,full-color reconstructions of complex natural images at a low sampling rate of 1%.In addition,APD-Net’s tuning-free nature ensures robustness across various imaging setups and sampling rates.Our research offers a broadly applicable approach for various applications,including but not limited to medical imaging and industrial inspection.展开更多
As the development of new power systems accelerates and the impacts of high renewable energy integration and extreme weather intensify,grid-alternative energy storage is garnering increasing attention for its grid-int...As the development of new power systems accelerates and the impacts of high renewable energy integration and extreme weather intensify,grid-alternative energy storage is garnering increasing attention for its grid-interaction benefits and clear business models.Consequently,assessing the value of grid-alternative energy storage in the systemtransition has become critically important.Considering the performance characteristics of storage,we propose a value assessment frame-work for grid-alternative energy storage,quantifying its non-wires-alternative effects from both cost and benefit perspectives.Building on this,we developed a collaborative planning model for energy storage and transmission grids,aimed at maximizing the economic benefits of storage systems while balancing investment and operational costs.The model considers regional grid interconnections and their interactions with system operation.By participating in system operations,grid-alternative energy storage not only maximizes its own economic benefits but also generates social welfare transfer effects.Furthermore,based on multi-regional interconnected planning,grid-alternative energy storage can reduce system costs by approximately 35%,with the most significant changes observed in generation costs.Multi-regional coordinated planning significantly enhances the sys-tem’s flexibility in regulation.However,when the load factor of interconnection lines between regions remains constant,system operational flexibility tends to decrease,leading to a roughly 28.9%increase in storage investment.Additionally,under regional coordinated planning,the greater the disparity in wind power integration across interconnected regions,the more noticeable the reduction in system costs.展开更多
The ring-opening alternating copolymerization(ROAC)of 3,4-dihydrocoumarin(DHC)/epoxides has been successfully developed using an imidazolium salt of 1-ethyl-3-methylimidazolium chloride(EMIMCl)as a catalyst.The result...The ring-opening alternating copolymerization(ROAC)of 3,4-dihydrocoumarin(DHC)/epoxides has been successfully developed using an imidazolium salt of 1-ethyl-3-methylimidazolium chloride(EMIMCl)as a catalyst.The resulting copolymer has a molecular weight of 13.7kg·mol^(-1),a narrow molecular weight distribution of 1.03 and a strictly alternating structure.The MALDI-TOF MS characterization and DFT calculations including electrostatic potential(ESP),hydrogen-atom abstraction(HAA),independent gradient model based on hirshfeld partition(IGMH)and atoms-in-molecules(AIM)analysis were used to investigate the metal-free catalytic process.The synergistic effect of anions and cations of EMIMCl for ROAC of DHC and epoxides was demonstrated.This study provides a metal-free catalytic system for the facile synthesis of alternating polyesters from DHC.展开更多
Prefabricated twinning represents an effective strategy for optimizing the microstructure of extruded forming components and facilitating changes in texture.The study examines the incorporation of[10-12]twins into an ...Prefabricated twinning represents an effective strategy for optimizing the microstructure of extruded forming components and facilitating changes in texture.The study examines the incorporation of[10-12]twins into an AZ31 magnesium alloy billet via cold pre-upsetting deformation before alternating forward extrusion(CUAFE).The experimental results indicate that the initial presence of[10-12]twins is advantageous for the development of[10-10]and[11-20]texture components during the extrusion process.In addition,different DRX mechanisms have different influences on the evolution of basal texture.The CDRX grains tend to preferentially select the[11-20]texture orientation,weakening the[10-10]texture and enhancing the[11-20]texture.However,most DDRX grains deviate significantly from the orientation of their surrounding original grain and do not have a preferred orientation.This is reflected in the mechanical properties of the CUAFE part.The tensile strength is 323.5 MPa,while the elongation is as high as 20.1%.展开更多
The results of the study of the effect of partial substitution of Fe by Mn in the La Fe_(11.2-x)Mn_(x)Co_(0.7)Si_(1.1)system on magnetization,specific heat,magnetostriction and magnetocaloric effect are presented.Dire...The results of the study of the effect of partial substitution of Fe by Mn in the La Fe_(11.2-x)Mn_(x)Co_(0.7)Si_(1.1)system on magnetization,specific heat,magnetostriction and magnetocaloric effect are presented.Direct measurements of the adiabatic temperature change(ΔT_(ad))were carried out in alternating magnetic fields(AMF)using the magnetic field modulation method.Partial substitution of Fe atoms by Mn atoms leads to a shift in the Curie temperature(T_(C))towards lower temperatures without a noticeable deterioration in magnetic properties.A correlation was found between the structural component of the magnetocaloric effect and the stability of the frequency of theΔT_(ad)in the AMFs—an increase in the manganese concentration leads to a decrease in magnetostriction and to a lower dependence ofΔT_(ad)on the frequency of the magnetic field.Estimates of the specific cooling power Q_(C)as a function of the frequency of the AMF showed that the highest value of Q_(C)at f=20 Hz in a magnetic field of 12k Oe is 26.3 W g^(-1)and is observed for the composition with x=0.1.This value is higher than that of Gd,for which,under the same conditions,Q_(C)=21.6 W g^(-1).All the samples studied show stability of the value ofΔT_(ad)without any sign of deterioration of the effect up to 60,000cycles of switching on/off of the magnetic field of 12 k Oe.The discovered frequency and cyclic stability ofΔT_(ad)of the studied samples increase their prospects for application in magnetic cooling technology.展开更多
Caspases,which play key roles in cell apoptosis,undergo alternative splicing to form different splicing variants that can regulate the apoptotic process.Lepidopteran insect caspases undergo alternative splicing,althou...Caspases,which play key roles in cell apoptosis,undergo alternative splicing to form different splicing variants that can regulate the apoptotic process.Lepidopteran insect caspases undergo alternative splicing,although the functions of their splicing variants are still unclear.The Spodoptera exigua caspase-5(SeCaspase-5)gene was cloned and found to produce four different splicing variants with different gene sequences and protein functional domains,which were named SeCaspase-5a,SeCaspase-5b,SeCaspase-5c and SeCaspase-5d.Overexpression of these variants in S.exigua cells(Se-3)showed that SeCaspase-5a had a proapoptotic function,whereas SeCaspase-5b,SeCaspase-5c and SeCaspase-5d did not.Semi-qPCR analysis revealed that the expression of the SeCaspase-5 variants significantly differed during Autographa californica multiple nucleopolyhedrovirus(AcMNPV)infection.Furthermore,the SeCaspase-5 variants were constructed into the AcMNPV bacmid and transfected into Se-3 cells,which revealed that SeCaspase-5a promoted cell apoptosis and reduced virus production,whereas SeCaspase-5b,SeCaspase-5c and SeCaspase-5d did not promote cell apoptosis but instead increased virus production.Moreover,an analysis of the interactions between the SeCaspase-5 variants revealed that SeCaspase-5a directly interacted with SeCaspase-5b,SeCaspase-5c and SeCaspase-5d.Coexpression of these variants in Se-3 cells also revealed that SeCaspase-5b,SeCaspase-5c and SeCaspase-5d inhibited the proapoptotic function of SeCaspase-5a,resulting in a reduction in the percentage of apoptotic cells by about 20%.These results indicate that SeCaspase-5 undergoes alternative splicing and is involved in regulating the apoptosis induced by baculovirus infection.These findings increase our understanding of the functions of lepidopteran insect caspases and provide new insights into the mechanism of host-cell apoptosis induced by baculoviruses.展开更多
Background With the global expansion of aquaculture and the increasing demand for fish meal,identifying appropriate and sustainable alternative protein sources for aquafeeds has become essential.Single-cell protein(SC...Background With the global expansion of aquaculture and the increasing demand for fish meal,identifying appropriate and sustainable alternative protein sources for aquafeeds has become essential.Single-cell protein(SCP),derived from methanotrophic bacteria,presents a promising alternative by converting methane into protein,potentially addressing both the need for alternative protein sources and reducing industrial greenhouse gas emissions.This study aimed to evaluate the effects of different levels of SCP inclusion(0%,25%,50%,and 75%fish meal replacement)on the health,gene expression,and gut microbiome of yellowtail kingfish(YTK,Seriola lalandi)following a 35-day growth trial.Results The study found that SCP inclusion at the highest level of fishmeal replacement(75%)induced a mild inflammatory response in the hindgut of the fish.However,micromorphological assessments of the hindgut,serum biochemistry,and gene expression analyses revealed no significant detrimental effects from SCP replacement.Notably,there were indications of improved lipid digestibility with SCP.Furthermore,SCP inclusion significantly enhanced microbial richness and altered the composition of the gut microbiome,introducing beneficial bacterial taxa that may contribute to improved gut health and resilience.Conclusions This study highlights SCP as a viable and sustainable alternative to fish meal in YTK diets.The findings suggest that SCP can be included in YTK diets without adverse health effects at moderate levels and may even offer benefits in terms of lipid digestibility and gut microbiome diversity.These results contribute to the advancement of more sustainable aquaculture practices.展开更多
The 2025 U.S.-China Trade War has intensified the vulnerability of China's oil supply chain due to heavy reliance on soybean imports,posing serious challenges to food security.This study examines soybean dependenc...The 2025 U.S.-China Trade War has intensified the vulnerability of China's oil supply chain due to heavy reliance on soybean imports,posing serious challenges to food security.This study examines soybean dependency risks and evaluates substitution strategies through diversified oilseed use,including palm-based alternatives.Findings show that high reciprocal tariffs caused a 75%drop in U.S.soybean exports to China.Palm oil,with high yield efficiency and cost-effectiveness,offers a viable supplement to fill supply chain gaps.Promoting oil palm cultivation through northward expansion and cooperation with Belt and Road countries is recommended.Additionally,multi-omics,gene editing,tissue culture,and precision agriculture are crucial to address technical bottlenecks.The study concludes that palm and soybean oils will form a complementary system,and that policy and technology investments are essential to strengthen China's oilseed supply chain resilience and sustainability.展开更多
The slow phase transition from formⅡto formⅠhas always been an important factor that restricts the processing and application of polybutene-1(PB-1).After extensive efforts,a set of effective methods for promoting th...The slow phase transition from formⅡto formⅠhas always been an important factor that restricts the processing and application of polybutene-1(PB-1).After extensive efforts,a set of effective methods for promoting the phase transition rate in PB-1 was established by adjusting the crystallization,nucleation,and growth temperatures.Nevertheless,low-molecular-weight PB-1(LMWPB-1)faces challenges because this method requires a low crystallization temperature,which is difficult to achieve during extrusion processing.In this study,we attempted to increase the phase transition rate in PB-1 by changing the annealing temperature after processing rather than the crystallization temperature in the classical scheme.The results indicated that regardless of low-or high-molecular-weight PB-1,repeated annealing between 0 and 90℃could also promote formⅡto formⅠphase transition.The initial content of formⅠincreased with the heating and cooling cycles.The half-time of the phase transition(t_(1/2))was also shortened after heating/cooling.After 100 heating/cooling cycles,t_(1/2) was reduced to one-quarter of that without annealing,which had almost the same effect as the crystallization temperature at 25℃in promoting the phase transition.This study indicates that annealing after processing is also an important factor affecting the phase transition of PB-1,and should receive sufficient attention.展开更多
The number of newborns born with diseases is increasing recently.Thyroid hormones(THs)are closely related to the growth and development of the newborn in the mother's womb and to the carriage of related diseases a...The number of newborns born with diseases is increasing recently.Thyroid hormones(THs)are closely related to the growth and development of the newborn in the mother's womb and to the carriage of related diseases after birth.Environmental endocrine-disrupting compounds(EDCs)have been proven to harm THs in newborns.Phthalates(PAEs),a typical class of EDCs,are commonly used in toys,childcare materials,and food contact materials,which have been closely connected with neonatal thyroid dysfunction and thyroid-related diseases.As restrictions on PAEs becomemore stringent in neonatal field,numerous PAE alternatives are emerging.Associations between exposure to PAEs and their alternatives and dysfunctions in THs have been explored.Hence,we summarized the body burdens and regional characteristics of PAEs and their alternatives in neonatal urine,cord blood,and meconium.Subsequently,the influences of PAEs and their alternatives on thyroid dysfunction,prematurity,low birth weight,fetal growth restriction,respiratory dysfunction,immune disorders,neurological disorders,and reproductive disorders in newborns were evaluated.Furthermore,we scrutinized the effects of PAEs and their alternatives on the neonatal thyroid from signaling,substance transport,and hormone production to explore the underlying mechanisms of action on neonatal thyroid and thyroid-related disorders.As the declining global trends of healthy newborns and the potential impacts of PAEs and their alternatives on thyroid function,a more comprehensive study is needed to discuss their effects on newborns and their underlying mechanisms.This review facilitates attention to the effects of PAEs and their alternatives on thyroid and thyroid-related disorders in newborns.展开更多
With the continuous advancement of electronic devices,flexible thin films with both thermal manage-ment functions and excellent electromagnetic interference(EMI)shielding properties have received much attention.Hence,...With the continuous advancement of electronic devices,flexible thin films with both thermal manage-ment functions and excellent electromagnetic interference(EMI)shielding properties have received much attention.Hence,inspired by Janus,a CNF/MXene/ZnFe2O4@PANI composite film with an asymmetric gradient alternating structure was successfully prepared by adjusting the filler content of the conduc-tive and magnetic layers using a vacuum-assisted filtration method.Benefiting from the magnetic reso-nance and hysteresis loss of ZnFe2O4@PANI,conductive loss and dipole polarization of MXene,as well as the exclusive"absorption-reflection-reabsorption"shielding feature in the alternating multilayered films,CM&CZFP-4 G film has superior EMI shielding performance,with an EMI SE of up to 45.75 dB and shield-ing effectiveness of 99.99%.Surprisingly,the composite film maintains reliable EMI shielding properties even after prolonged erosion in harsh environments such as high/low temperatures,high humidity,acids and alkalis.Furthermore,the CM&CZFP-4 G responded quickly within about 50 s and reached a maximum steady-state temperature of 235.8℃ at an applied voltage of 9.0 V,indicating the obtained film acquired outstanding and controllable Joule heating performance.This result was attributed to the homogeneous dispersion of MXene to build up a conductive network and endow the CNF/MXene with high conduc-tivity.Meanwhile,the fire resistance of CM&CZFP-4 G was significantly improved compared to pure CNF,which guaranteed fire safety during its application.Additionally,contributed by long fiber entanglement of CNF,extensive hydrogen-bonding interactions and multilayer structural design,the CM&CZFP-4 G film exhibits excellent mechanical characteristics,with the tensile strength and fracture strain of 27.74 MPa and 6.21%,separately.This work offers a creative avenue to prepare multifunctional composite films with electromagnetic shielding and Joule heating for various application environments.展开更多
Heat stress is a major threat to maize(Zea mays L.)production worldwide.Heat shock transcription factors(HSFs)play vital roles in plant responses to heat stress.However,the molecular and genetic mechanisms underlying ...Heat stress is a major threat to maize(Zea mays L.)production worldwide.Heat shock transcription factors(HSFs)play vital roles in plant responses to heat stress.However,the molecular and genetic mechanisms underlying HSF-meditated thermotolerance in maize remain largely unexplored.In this study,we demonstrate that the alternative splicing of ZmHsf23 modulates heat stress tolerance in maize.Hsf23 produced two functional transcripts,Hsf23L and Hsf23S,which differ by the presence of a cryptic mini-exon in Hsf23L that is spliced out in Hsf23S.Both transcripts were strongly induced by heat stress.Mutants lacking Hsf23L alone(hsf23l)or both Hsf23L and Hsf23S(hsf23l23s)exhibited increased susceptibility to heat stress,whereas overexpression of Hsf23S enhanced heat stress tolerance in maize.Subsequently,we found that Hsf23S positively regulates heat stress tolerance by directly activating the transcription of three sHSP genes(Hsp16.9,Hsp17.2,and Hsp18a)and TIL1 gene.In addition,Hsf23L physically interacted with Hsf23S and enhanced the transcriptional activation of Hsf23S on the sHSPs and TIL1 promoters.Notably,genetic analysis suggested that co-overexpression of Hsf23L and Hsf23S further improves heat tolerance of the transgenic plants.Taken together,these results reveal two splicing variants of ZmHsf23 cooperatively regulate maize heat tolerance,thus highlighting potential value of ZmHsf23 in breeding heat-tolerant maize varieties.展开更多
Somatic variants in the cancer genome influence gene expression through diverse mechanisms depending on their specific locations.However,a systematic evaluation of the effects of somatic variants located in 3'untr...Somatic variants in the cancer genome influence gene expression through diverse mechanisms depending on their specific locations.However,a systematic evaluation of the effects of somatic variants located in 3'untranslated regions(3'UTRs)on alternative polyadenylation(APA)of m RNA remains lacking.In this study,we analyze 10,199 tumor samples across 32 cancer types and identify 1333 somatic single nucleotide variants(SNVs)associated with abnormal 3'UTR APA.Mechanistically,these 3'UTR SNVs can alter cisregulatory elements,such as the poly(A)signal and UGUA motif,leading to changes in APA.Minigene assays confirm that 3'UTR SNVs in multiple genes,including RPS23 and CHTOP,induce aberrant APA.Among affected genes,62 exhibit differential stability between tandem 3'UTR isoforms,including HSPA4and UCK2,validated by experimental assays.Finally,we establish that SNV-related abnormal APA usage serves as an additional layer of expression regulation for tumor-suppressor gene HMGN2 in breast cancer.Collectively,this study reveals 3'UTR APA as a critical mechanism mediating the functional impact of somatic noncoding variants in human cancers.展开更多
文摘As a newly developed precision technology, casting-forging complex near net forming process is utilized to produce complex components with a short lead time, low cost and high precision, thus to accelerate the response speed of the market and enhance the competitive power of products. In this paper, the casting-forging complex near net forming process of alternator claw pole was developed and investigated with a combination of experimental and numerical simulation method. Qualified near net workpiece was manufactured, mechanical parameter and relative field information during the forming process was also obtained. While the alternator claw-pole is processed with this technology, the forming force is small, the process is short and the quality of forgings is perfect. Therefore, the complex casting-forging near net forming process of claw-pole is an energy and material saving technology, which will have a vast developing and application prospect in the future.
基金Supported by the National Natural Science Foundation of China(50337030)the Natural Science Foundation of Shanghai(08ZR1408600)the Natural Science Foundation of Shanghai Dianji University(08C410)~~
文摘To solve the low efficiency of electric excitation claw-pole synchronous generator（EECPSG） and regulate the magnetic field of permanent magnet （PM） claw-pole synchronous generator（PMCPSG）, a novel hybrid excitation claw-pole synchronous generator （HECPSG）with magnetic circuit series connection is proposed. Through the simulation study on the generator using the calculation method for magnetic circuit and 3-D finite element method （FEA）, the appropriate magnet thickness and the number of pole-pairs for the proposed generator are determined. Its off-loading characteristics, load characteristics, and regulation behaviors are investigated. The study shows that the appropriate number of pole-pairs in HECPSG with series magnetic circuits is two, and there exists an optimum magnet thickness. Compared to EECPSG, HECPSG realizes dual-directional control to the excitation current. Moreover, the generator can adjust the output voltage and keep the output voltage stable in a broad load range. Under the condition of same parametes, the motor has higer air-gap flux density and power density.
文摘The casting-forging combined technique and the closed die forging without flash-less are both new developed material working methods. The former can not only decrease forming operations of forgings, but also increase the material utilization ratio. Therefore, it is applied to produce more complex forgings. The latter is required for forging precise parts without burrs. The alternator pole is a complex forging, which was usually produced by hot forging, upsetting-extrusion or upsetting-extrusion and bending processes. During these processes, not only the forming force is higher, but the material of burrs accounts for 30 percent or so of total required material. And burrs are difficult to remove in the sequential machining process. In accordance with defects exiting in current manufacturing of alternator poles by upsetting-extruding process, such as more material demand, higher forming force and difficulty of next machining, a casting-forging precision process of alternator poles was developed and investigated in this paper. In the process, the pole was formed by two operations. One is the pre-forming operation by casting. The other is the final forming operation by the closed precision forging process. This can not only shorten processes, decrease material and power demand, but also increase precision of forgings. First, the casting blocker was designed considering the casting process and the forging ratio and the mode of deformation. Then the die structure for closed precision forging was designed, and the closing device for forging dies with spring assemblies in order to provide the necessary closing force was also designed. Finally the forming processes was investigated by test and numerical simulation method to optimum process parameters and die structure design parameters. The result can provide basis for applying the process to manufacture poles in practice.
文摘Based on the structure analysis of alternator poles, two closed die forging steps in one heat forming process of alternator poles were put forward, as well as the forming die system. Firstly, a thicker bottom base of alternator poles was per-formed by radial forging, then the middle boss and pole claw were forming on the bottom base by backward extrusion. A 3-D coupled thermo-mechanical finite element model was created. The billet deformation, metal flow and forming load were obtained. The results showed that a filling well forging without overlap defects could be obtained by this process, and that?the forming load at the first step increased slowly, but the load increased sharply at the second step when the middle boss was filling completely by the former process. An improved process was put forward, which changed the flow mode in the second forging step, it can considerably reduce the final forging load.
基金Project (No. 50806046) supported by the National Natural Science Foundation of China
文摘We proposed the flat-type permanent magnet linear alternator (LA) for free piston linear alternators (FPLAs) instead of the tubular one. Using the finite element method (FEM), we compare these two kinds of LAs. The FEM result shows that the flat-type permanent magnet LA has higher efficiency and larger output specific power than the tubular one, therefore more suitable for FPLAs, and that the alternator design can be optimized with respect to the permanent magnet length as well as the air gap.
基金This work was supported by the Natural Science Foundation of China under Grant 51307031 and part by the Natural Science Foundation of Heilongjiang Province under Grant E2018034 and China Postdoctoral Science Foundation funded project under Grant 2019M651185.
文摘Demagnetization behavior of Halbach magnetized compensated pulsed alternator(CPA)is studied by using finite element method(FEM)under the different demagnetization factors in this paper.The effect of armature reaction magnetic field and thermal rise on demagnetization of PMs is analyzed.This paper investigates the effect of different demagnetization factors on magnetic field distribution,load current,and no-load phase voltage.A series of dynamic demagnetization points in Halbach array permanent magnet(PM)are evaluated to search the worst working point.Partial demagnetization risk can be represented by the worst working point,and the global demagnetization of the PM is represented by the no-load phase voltage characteristics after discharge.The research results demonstrated that the compensation shield with a certain thickness can increase the discharge current and weaken the demagnetization influence of armature reaction.The demagnetization effect of armature reaction on PMs at high temperatures will be strengthened.
基金upported by the National Natural Science Foundation of China(Grant No.62305184)the Major Key Project of Pengcheng Laboratory(Grant No.PCL2024A1)+1 种基金the Basic and Applied Basic Research Foundation of Guangdong Province(Grant No.2023A1515012932)the Science,Technology and Innovation Commission of Shenzhen Municipality(Grant No.WDZC20220818100259004).
文摘Single-pixel imaging(SPI)enables efficient sensing in challenging conditions.However,the requirement for numerous samplings constrains its practicality.We address the challenge of high-quality SPI reconstruction at ultra-low sampling rates.We develop an alternative optimization with physics and a data-driven diffusion network(APD-Net).It features alternative optimization driven by the learned task-agnostic natural image prior and the task-specific physics prior.During the training stage,APD-Net harnesses the power of diffusion models to capture data-driven statistics of natural signals.In the inference stage,the physics prior is introduced as corrective guidance to ensure consistency between the physics imaging model and the natural image probability distribution.Through alternative optimization,APD-Net reconstructs data-efficient,high-fidelity images that are statistically and physically compliant.To accelerate reconstruction,initializing images with the inverse SPI physical model reduces the need for reconstruction inference from 100 to 30 steps.Through both numerical simulations and real prototype experiments,APD-Net achieves high-quality,full-color reconstructions of complex natural images at a low sampling rate of 1%.In addition,APD-Net’s tuning-free nature ensures robustness across various imaging setups and sampling rates.Our research offers a broadly applicable approach for various applications,including but not limited to medical imaging and industrial inspection.
基金funded by the Technology Project of State Grid Jibei Electric Power Supply Co.,Ltd.(Grant Number:52018F240001).
文摘As the development of new power systems accelerates and the impacts of high renewable energy integration and extreme weather intensify,grid-alternative energy storage is garnering increasing attention for its grid-interaction benefits and clear business models.Consequently,assessing the value of grid-alternative energy storage in the systemtransition has become critically important.Considering the performance characteristics of storage,we propose a value assessment frame-work for grid-alternative energy storage,quantifying its non-wires-alternative effects from both cost and benefit perspectives.Building on this,we developed a collaborative planning model for energy storage and transmission grids,aimed at maximizing the economic benefits of storage systems while balancing investment and operational costs.The model considers regional grid interconnections and their interactions with system operation.By participating in system operations,grid-alternative energy storage not only maximizes its own economic benefits but also generates social welfare transfer effects.Furthermore,based on multi-regional interconnected planning,grid-alternative energy storage can reduce system costs by approximately 35%,with the most significant changes observed in generation costs.Multi-regional coordinated planning significantly enhances the sys-tem’s flexibility in regulation.However,when the load factor of interconnection lines between regions remains constant,system operational flexibility tends to decrease,leading to a roughly 28.9%increase in storage investment.Additionally,under regional coordinated planning,the greater the disparity in wind power integration across interconnected regions,the more noticeable the reduction in system costs.
基金financially supported by the National Natural Science Foundation of China(No.22161040)Natural Science Foundation of Gansu(No.24JRRA125)Science Research Project of Northwest Normal University(No.NWNU-LKZD2021-3)。
文摘The ring-opening alternating copolymerization(ROAC)of 3,4-dihydrocoumarin(DHC)/epoxides has been successfully developed using an imidazolium salt of 1-ethyl-3-methylimidazolium chloride(EMIMCl)as a catalyst.The resulting copolymer has a molecular weight of 13.7kg·mol^(-1),a narrow molecular weight distribution of 1.03 and a strictly alternating structure.The MALDI-TOF MS characterization and DFT calculations including electrostatic potential(ESP),hydrogen-atom abstraction(HAA),independent gradient model based on hirshfeld partition(IGMH)and atoms-in-molecules(AIM)analysis were used to investigate the metal-free catalytic process.The synergistic effect of anions and cations of EMIMCl for ROAC of DHC and epoxides was demonstrated.This study provides a metal-free catalytic system for the facile synthesis of alternating polyesters from DHC.
基金supported by the National Natural Science Foundation of China(No.52475341).
文摘Prefabricated twinning represents an effective strategy for optimizing the microstructure of extruded forming components and facilitating changes in texture.The study examines the incorporation of[10-12]twins into an AZ31 magnesium alloy billet via cold pre-upsetting deformation before alternating forward extrusion(CUAFE).The experimental results indicate that the initial presence of[10-12]twins is advantageous for the development of[10-10]and[11-20]texture components during the extrusion process.In addition,different DRX mechanisms have different influences on the evolution of basal texture.The CDRX grains tend to preferentially select the[11-20]texture orientation,weakening the[10-10]texture and enhancing the[11-20]texture.However,most DDRX grains deviate significantly from the orientation of their surrounding original grain and do not have a preferred orientation.This is reflected in the mechanical properties of the CUAFE part.The tensile strength is 323.5 MPa,while the elongation is as high as 20.1%.
基金financially supported by Russian Science Foundation(No.24-43-00156,https://rscf.ru/en/project/24-43-00156/)the National Natural Science Foundation of China(No.52171169)the State Key Laboratory for Advanced Metals and Materials(No.2023-ZD01)。
文摘The results of the study of the effect of partial substitution of Fe by Mn in the La Fe_(11.2-x)Mn_(x)Co_(0.7)Si_(1.1)system on magnetization,specific heat,magnetostriction and magnetocaloric effect are presented.Direct measurements of the adiabatic temperature change(ΔT_(ad))were carried out in alternating magnetic fields(AMF)using the magnetic field modulation method.Partial substitution of Fe atoms by Mn atoms leads to a shift in the Curie temperature(T_(C))towards lower temperatures without a noticeable deterioration in magnetic properties.A correlation was found between the structural component of the magnetocaloric effect and the stability of the frequency of theΔT_(ad)in the AMFs—an increase in the manganese concentration leads to a decrease in magnetostriction and to a lower dependence ofΔT_(ad)on the frequency of the magnetic field.Estimates of the specific cooling power Q_(C)as a function of the frequency of the AMF showed that the highest value of Q_(C)at f=20 Hz in a magnetic field of 12k Oe is 26.3 W g^(-1)and is observed for the composition with x=0.1.This value is higher than that of Gd,for which,under the same conditions,Q_(C)=21.6 W g^(-1).All the samples studied show stability of the value ofΔT_(ad)without any sign of deterioration of the effect up to 60,000cycles of switching on/off of the magnetic field of 12 k Oe.The discovered frequency and cyclic stability ofΔT_(ad)of the studied samples increase their prospects for application in magnetic cooling technology.
基金funded by the National Natural Science Foundation of China(32202393)the Natural Science Foundation of Shandong Province,China(ZR2021QC190)+1 种基金the Science and Technology Benefiting the People Demonstration Project of Qingdao,China(24-1-8-xdny-10-nsh)the Qingdao Agricultural University High-level Talent Fund,China(663/1120101)。
文摘Caspases,which play key roles in cell apoptosis,undergo alternative splicing to form different splicing variants that can regulate the apoptotic process.Lepidopteran insect caspases undergo alternative splicing,although the functions of their splicing variants are still unclear.The Spodoptera exigua caspase-5(SeCaspase-5)gene was cloned and found to produce four different splicing variants with different gene sequences and protein functional domains,which were named SeCaspase-5a,SeCaspase-5b,SeCaspase-5c and SeCaspase-5d.Overexpression of these variants in S.exigua cells(Se-3)showed that SeCaspase-5a had a proapoptotic function,whereas SeCaspase-5b,SeCaspase-5c and SeCaspase-5d did not.Semi-qPCR analysis revealed that the expression of the SeCaspase-5 variants significantly differed during Autographa californica multiple nucleopolyhedrovirus(AcMNPV)infection.Furthermore,the SeCaspase-5 variants were constructed into the AcMNPV bacmid and transfected into Se-3 cells,which revealed that SeCaspase-5a promoted cell apoptosis and reduced virus production,whereas SeCaspase-5b,SeCaspase-5c and SeCaspase-5d did not promote cell apoptosis but instead increased virus production.Moreover,an analysis of the interactions between the SeCaspase-5 variants revealed that SeCaspase-5a directly interacted with SeCaspase-5b,SeCaspase-5c and SeCaspase-5d.Coexpression of these variants in Se-3 cells also revealed that SeCaspase-5b,SeCaspase-5c and SeCaspase-5d inhibited the proapoptotic function of SeCaspase-5a,resulting in a reduction in the percentage of apoptotic cells by about 20%.These results indicate that SeCaspase-5 undergoes alternative splicing and is involved in regulating the apoptosis induced by baculovirus infection.These findings increase our understanding of the functions of lepidopteran insect caspases and provide new insights into the mechanism of host-cell apoptosis induced by baculoviruses.
基金Fisheries Research Development Corporation,Grant/Award Number:2017-030.
文摘Background With the global expansion of aquaculture and the increasing demand for fish meal,identifying appropriate and sustainable alternative protein sources for aquafeeds has become essential.Single-cell protein(SCP),derived from methanotrophic bacteria,presents a promising alternative by converting methane into protein,potentially addressing both the need for alternative protein sources and reducing industrial greenhouse gas emissions.This study aimed to evaluate the effects of different levels of SCP inclusion(0%,25%,50%,and 75%fish meal replacement)on the health,gene expression,and gut microbiome of yellowtail kingfish(YTK,Seriola lalandi)following a 35-day growth trial.Results The study found that SCP inclusion at the highest level of fishmeal replacement(75%)induced a mild inflammatory response in the hindgut of the fish.However,micromorphological assessments of the hindgut,serum biochemistry,and gene expression analyses revealed no significant detrimental effects from SCP replacement.Notably,there were indications of improved lipid digestibility with SCP.Furthermore,SCP inclusion significantly enhanced microbial richness and altered the composition of the gut microbiome,introducing beneficial bacterial taxa that may contribute to improved gut health and resilience.Conclusions This study highlights SCP as a viable and sustainable alternative to fish meal in YTK diets.The findings suggest that SCP can be included in YTK diets without adverse health effects at moderate levels and may even offer benefits in terms of lipid digestibility and gut microbiome diversity.These results contribute to the advancement of more sustainable aquaculture practices.
基金financially sponsored by Hainan Provincial Natural Science Foundation(324QN360)Project of Sanya Yazhou Bay Sci-ence and Technology City(SCKJ-JYRC-2024-35).
文摘The 2025 U.S.-China Trade War has intensified the vulnerability of China's oil supply chain due to heavy reliance on soybean imports,posing serious challenges to food security.This study examines soybean dependency risks and evaluates substitution strategies through diversified oilseed use,including palm-based alternatives.Findings show that high reciprocal tariffs caused a 75%drop in U.S.soybean exports to China.Palm oil,with high yield efficiency and cost-effectiveness,offers a viable supplement to fill supply chain gaps.Promoting oil palm cultivation through northward expansion and cooperation with Belt and Road countries is recommended.Additionally,multi-omics,gene editing,tissue culture,and precision agriculture are crucial to address technical bottlenecks.The study concludes that palm and soybean oils will form a complementary system,and that policy and technology investments are essential to strengthen China's oilseed supply chain resilience and sustainability.
基金financially supported by the National Natural Science Foundation of China(No.22175183)。
文摘The slow phase transition from formⅡto formⅠhas always been an important factor that restricts the processing and application of polybutene-1(PB-1).After extensive efforts,a set of effective methods for promoting the phase transition rate in PB-1 was established by adjusting the crystallization,nucleation,and growth temperatures.Nevertheless,low-molecular-weight PB-1(LMWPB-1)faces challenges because this method requires a low crystallization temperature,which is difficult to achieve during extrusion processing.In this study,we attempted to increase the phase transition rate in PB-1 by changing the annealing temperature after processing rather than the crystallization temperature in the classical scheme.The results indicated that regardless of low-or high-molecular-weight PB-1,repeated annealing between 0 and 90℃could also promote formⅡto formⅠphase transition.The initial content of formⅠincreased with the heating and cooling cycles.The half-time of the phase transition(t_(1/2))was also shortened after heating/cooling.After 100 heating/cooling cycles,t_(1/2) was reduced to one-quarter of that without annealing,which had almost the same effect as the crystallization temperature at 25℃in promoting the phase transition.This study indicates that annealing after processing is also an important factor affecting the phase transition of PB-1,and should receive sufficient attention.
基金supported by the National Natural Science Foundation of China(No.22225605)the National Key Research and Development Program of China(No.2023YFC3706600)the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB0750200).
文摘The number of newborns born with diseases is increasing recently.Thyroid hormones(THs)are closely related to the growth and development of the newborn in the mother's womb and to the carriage of related diseases after birth.Environmental endocrine-disrupting compounds(EDCs)have been proven to harm THs in newborns.Phthalates(PAEs),a typical class of EDCs,are commonly used in toys,childcare materials,and food contact materials,which have been closely connected with neonatal thyroid dysfunction and thyroid-related diseases.As restrictions on PAEs becomemore stringent in neonatal field,numerous PAE alternatives are emerging.Associations between exposure to PAEs and their alternatives and dysfunctions in THs have been explored.Hence,we summarized the body burdens and regional characteristics of PAEs and their alternatives in neonatal urine,cord blood,and meconium.Subsequently,the influences of PAEs and their alternatives on thyroid dysfunction,prematurity,low birth weight,fetal growth restriction,respiratory dysfunction,immune disorders,neurological disorders,and reproductive disorders in newborns were evaluated.Furthermore,we scrutinized the effects of PAEs and their alternatives on the neonatal thyroid from signaling,substance transport,and hormone production to explore the underlying mechanisms of action on neonatal thyroid and thyroid-related disorders.As the declining global trends of healthy newborns and the potential impacts of PAEs and their alternatives on thyroid function,a more comprehensive study is needed to discuss their effects on newborns and their underlying mechanisms.This review facilitates attention to the effects of PAEs and their alternatives on thyroid and thyroid-related disorders in newborns.
基金supported by the National Natural Science Foundation of China(Nos.22005277,52474256 and 52074247)the Natural Science Foundation of Hubei Province(No.2024AFB662)+1 种基金the Young Top-notch Talent Cultivation Program of Hubei Province,Opening Foundation of State Key Laboratory of Organic-Inorganic Composites,Beijing University of Chemical Technology(No.oic-202401012)the Fundamental Research Funds for National Universities,China University of Geosciences(No.2024XLA93).
文摘With the continuous advancement of electronic devices,flexible thin films with both thermal manage-ment functions and excellent electromagnetic interference(EMI)shielding properties have received much attention.Hence,inspired by Janus,a CNF/MXene/ZnFe2O4@PANI composite film with an asymmetric gradient alternating structure was successfully prepared by adjusting the filler content of the conduc-tive and magnetic layers using a vacuum-assisted filtration method.Benefiting from the magnetic reso-nance and hysteresis loss of ZnFe2O4@PANI,conductive loss and dipole polarization of MXene,as well as the exclusive"absorption-reflection-reabsorption"shielding feature in the alternating multilayered films,CM&CZFP-4 G film has superior EMI shielding performance,with an EMI SE of up to 45.75 dB and shield-ing effectiveness of 99.99%.Surprisingly,the composite film maintains reliable EMI shielding properties even after prolonged erosion in harsh environments such as high/low temperatures,high humidity,acids and alkalis.Furthermore,the CM&CZFP-4 G responded quickly within about 50 s and reached a maximum steady-state temperature of 235.8℃ at an applied voltage of 9.0 V,indicating the obtained film acquired outstanding and controllable Joule heating performance.This result was attributed to the homogeneous dispersion of MXene to build up a conductive network and endow the CNF/MXene with high conduc-tivity.Meanwhile,the fire resistance of CM&CZFP-4 G was significantly improved compared to pure CNF,which guaranteed fire safety during its application.Additionally,contributed by long fiber entanglement of CNF,extensive hydrogen-bonding interactions and multilayer structural design,the CM&CZFP-4 G film exhibits excellent mechanical characteristics,with the tensile strength and fracture strain of 27.74 MPa and 6.21%,separately.This work offers a creative avenue to prepare multifunctional composite films with electromagnetic shielding and Joule heating for various application environments.
基金supported by the National Key Research and Development Program of China(2021YFF1000301)the National Natural Science Foundation of China(31771805)。
文摘Heat stress is a major threat to maize(Zea mays L.)production worldwide.Heat shock transcription factors(HSFs)play vital roles in plant responses to heat stress.However,the molecular and genetic mechanisms underlying HSF-meditated thermotolerance in maize remain largely unexplored.In this study,we demonstrate that the alternative splicing of ZmHsf23 modulates heat stress tolerance in maize.Hsf23 produced two functional transcripts,Hsf23L and Hsf23S,which differ by the presence of a cryptic mini-exon in Hsf23L that is spliced out in Hsf23S.Both transcripts were strongly induced by heat stress.Mutants lacking Hsf23L alone(hsf23l)or both Hsf23L and Hsf23S(hsf23l23s)exhibited increased susceptibility to heat stress,whereas overexpression of Hsf23S enhanced heat stress tolerance in maize.Subsequently,we found that Hsf23S positively regulates heat stress tolerance by directly activating the transcription of three sHSP genes(Hsp16.9,Hsp17.2,and Hsp18a)and TIL1 gene.In addition,Hsf23L physically interacted with Hsf23S and enhanced the transcriptional activation of Hsf23S on the sHSPs and TIL1 promoters.Notably,genetic analysis suggested that co-overexpression of Hsf23L and Hsf23S further improves heat tolerance of the transgenic plants.Taken together,these results reveal two splicing variants of ZmHsf23 cooperatively regulate maize heat tolerance,thus highlighting potential value of ZmHsf23 in breeding heat-tolerant maize varieties.
基金financially supported by the National Key R&D Program of China(2023YFC3603300,2021YFA0909300)National Natural Science Foundation of China(92249302,32370592,32400437)China Postdoctoral Science Foundation(BX20230073 and 2023M740709)。
文摘Somatic variants in the cancer genome influence gene expression through diverse mechanisms depending on their specific locations.However,a systematic evaluation of the effects of somatic variants located in 3'untranslated regions(3'UTRs)on alternative polyadenylation(APA)of m RNA remains lacking.In this study,we analyze 10,199 tumor samples across 32 cancer types and identify 1333 somatic single nucleotide variants(SNVs)associated with abnormal 3'UTR APA.Mechanistically,these 3'UTR SNVs can alter cisregulatory elements,such as the poly(A)signal and UGUA motif,leading to changes in APA.Minigene assays confirm that 3'UTR SNVs in multiple genes,including RPS23 and CHTOP,induce aberrant APA.Among affected genes,62 exhibit differential stability between tandem 3'UTR isoforms,including HSPA4and UCK2,validated by experimental assays.Finally,we establish that SNV-related abnormal APA usage serves as an additional layer of expression regulation for tumor-suppressor gene HMGN2 in breast cancer.Collectively,this study reveals 3'UTR APA as a critical mechanism mediating the functional impact of somatic noncoding variants in human cancers.
