Neural machine interface technology is a pioneering approach that aims to address the complex challenges of neurological dysfunctions and disabilities resulting from conditions such as congenital disorders,traumatic i...Neural machine interface technology is a pioneering approach that aims to address the complex challenges of neurological dysfunctions and disabilities resulting from conditions such as congenital disorders,traumatic injuries,and neurological diseases.Neural machine interface technology establishes direct connections with the brain or peripheral nervous system to restore impaired motor,sensory,and cognitive functions,significantly improving patients'quality of life.This review analyzes the chronological development and integration of various neural machine interface technologies,including regenerative peripheral nerve interfaces,targeted muscle and sensory reinnervation,agonist–antagonist myoneural interfaces,and brain–machine interfaces.Recent advancements in flexible electronics and bioengineering have led to the development of more biocompatible and highresolution electrodes,which enhance the performance and longevity of neural machine interface technology.However,significant challenges remain,such as signal interference,fibrous tissue encapsulation,and the need for precise anatomical localization and reconstruction.The integration of advanced signal processing algorithms,particularly those utilizing artificial intelligence and machine learning,has the potential to improve the accuracy and reliability of neural signal interpretation,which will make neural machine interface technologies more intuitive and effective.These technologies have broad,impactful clinical applications,ranging from motor restoration and sensory feedback in prosthetics to neurological disorder treatment and neurorehabilitation.This review suggests that multidisciplinary collaboration will play a critical role in advancing neural machine interface technologies by combining insights from biomedical engineering,clinical surgery,and neuroengineering to develop more sophisticated and reliable interfaces.By addressing existing limitations and exploring new technological frontiers,neural machine interface technologies have the potential to revolutionize neuroprosthetics and neurorehabilitation,promising enhanced mobility,independence,and quality of life for individuals with neurological impairments.By leveraging detailed anatomical knowledge and integrating cutting-edge neuroengineering principles,researchers and clinicians can push the boundaries of what is possible and create increasingly sophisticated and long-lasting prosthetic devices that provide sustained benefits for users.展开更多
One of the most widely used and well-established atomic oxygen(AO)protection solutions for low Earth orbit(LEO)satellites is the deposition of protective coatings on polymeric materials.However,manufacturing extensive...One of the most widely used and well-established atomic oxygen(AO)protection solutions for low Earth orbit(LEO)satellites is the deposition of protective coatings on polymeric materials.However,manufacturing extensive expanses of these coating materials with good transparency,flexibility,smoothness,ultra-thinness,and exceptional AO resistance remains a critical issue.Herein,we successfully deposited a 400 nm thick polyorgansiloxane(SiO_(x)C_(y)H_(z))coating with high optical transparency and uniform good adherence on to a 1.2 m wide polyimide surface,by optimizing the distribution of hexamethyldisiloxane and oxygen as precursors in the roll-to-roll compatible plasmaenhanced chemical vapor deposition process.After AO irradiation with the fluence of 7.9×10^(20)atoms·cm^(–2),the erosion yield of the SiO_(x)C_(y)H_(z)-coated Kapton was less than 2.30×10^(–26)cm^3·atom^(–1),which was less than 0.77%of that of the Kapton.It indicates that the SiO_(x)C_(y)H_(z)coating can well prevent the erosion of Kapton by AO.In addition,it was also clarified that a SiO_(2) passivation layer was formed on the surface of the SiO_(x)C_(y)H_(z)coating during AO irradiation,which exhibited a‘self-reinforcing’defense mechanism.The entire preparation process of the SiO_(x)C_(y)H_(z)coating was highly efficient and low-cost,and it has shown great potential for applications in LEO.展开更多
Cotton fiber is one of the main raw materials for the textile industry.In recent years,many cotton fiber quality QTL have been identified,but few were applied in breeding.In this study,a genome wide association study(...Cotton fiber is one of the main raw materials for the textile industry.In recent years,many cotton fiber quality QTL have been identified,but few were applied in breeding.In this study,a genome wide association study(GWAS)of fiber-quality traits in 265 upland cotton breeding intermediate lines(GhBreeding),combined with genome-wide selective sweep analysis(GSSA)and genomic selection(GS),revealed 25 QTL.Most of these QTL were ignored by only using GWAS.The CRISPR/Cas9 mutants of GhMYB_D13 had shorter fiber,which indicates the credibility of QTL to a certain extent.Then these QTL were verified in other cotton natural populations,5 stable QTL were found having broad potential for application in breeding.Additionally,among these 5 stable QTL,superior genotypes of 4 showed an enrichment in most improved new varieties widely cultivated currently.These findings provide insights for how to identify more QTL through combined multiple genomic analysis to apply in breeding.展开更多
Isostructural multicomponent crystals provide a promising way for fine-tuning physicochemical properties, whereas their design remains quite challenging. The purpose of this work was to provide a new strategy for obta...Isostructural multicomponent crystals provide a promising way for fine-tuning physicochemical properties, whereas their design remains quite challenging. The purpose of this work was to provide a new strategy for obtaining isostructural multicomponent crystals by introducing coformers with functional group positional isomerism. Five isostructural salts of an antitumor drug dimethylaminomicheliolide(DMAMCL) were reported and designed with a series of dihydroxybenzoic acid regioisomers for the first time, which were identified by power and single-crystal X-ray diffractions. Similar lattice parameters suggested these obtained salts may have the same crystal packing mode. The quantitative similarity parameters via XPac, Crystal CMP and Mercury program further proved these crystal structures are3D isostructural. Hirshfeld surface maps and 2D fingerprint plots show that the isostructural salts have similar intermolecular interactions. Compared with DMAMCL, obvious improvement was observed in the thermal stability, hygroscopicity, and solubility of these isostructural salts. Meanwhile, isostructural crystals may have different physicochemical properties, even though the shape and molecular size are similar and the packing of crystal structures is equally matched.展开更多
The co-crystallization of quercetin(Qur)with a flexible molecule 4-(4-pyridinyldisulfanyl)pyridine(DPDS)in different solvents and conditions was investigated,yielded five multi-component crystalline phases and charact...The co-crystallization of quercetin(Qur)with a flexible molecule 4-(4-pyridinyldisulfanyl)pyridine(DPDS)in different solvents and conditions was investigated,yielded five multi-component crystalline phases and characterized with X-ray diffractions and thermal analysis.Although the crystal system of Qur-DPDSMe OH and Qur-DPDS-Dioxane is the same,the desolvation results revealed that Qur-DPDS-Me OH transformed to Qur-DPDS when Me OH solvent molecules escape from the lattice,while Qur-DPDS-Dioxane transformed to Qur-DPDS-II through a similar process,which is same with Qur-DPDS-THF.These two cocrystal polymorphs Qur-DPDS and Qur-DPDS-II obey an enantiotropic relationship.Moreover,the formation of cocrystal solvates improves the packing efficiency of crystals.Crystal structure analysis showed that hydrogen bonds and conformations of the corresponding parent molecules play a major role in molecular assembly and crystal packing patterns,thus bring different physicochemical properties.Finally,the fluorescence spectra and quantum-chemical calculations were carried out to explore the difference in the optical-physical properties.展开更多
The integration of machine learning and electrocatalysis presents nota ble advancements in designing and predicting the performance of chiral materials for hydrogen evolution reactions(HER).This study utilizes theoret...The integration of machine learning and electrocatalysis presents nota ble advancements in designing and predicting the performance of chiral materials for hydrogen evolution reactions(HER).This study utilizes theoretical calculations and machine learning techniques to assess the HER performance of both chiral and achiral M-N-SWCNTs(M=In,Bi,and Sb)single-atom catalysts(SACs).The stability preferences of metal atoms are dependent on chirality when interacting with chiral SWCNTs.The HER activity of the right-handed In-N-SWCNT is 5.71 times greater than its achiral counterpart,whereas the left-handed In-N-SWCNT exhibits a 5.12-fold enhancement.The calculated hydrogen adsorption free energy for the right-handed In-N-SWCNT reaches as low as-0.02 eV.This enhancement is attributed to the symmetry breaking in spin density distribution,transitioning from C_(2V)in achiral SACs to C_(2)in chiral SACs,which facilitates active site transfer and enhances local spin density.Right-handed M-N-SWCNTs exhibit superiorα-electron separation and transport efficiency relative to left-handed variants,owing to the chiral induced spin selectivity(CISS)effect,with spin-upα-electron density reaching 3.43×10^(-3)e/Bohr^(3)at active sites.Machine learning provides deeper insights,revealing that the interplay of weak spatial electronic effects and appropriate curvature-chirality effects significantly enhances HER performance.A weaker spatial electronic effect correlates with higher HER activity,larger exchange current density,and higher turnover frequency.The curvature-chirality effect undersco res the influence of intrinsic structures on HER performance.These findings offer critical insights into the role of chirality in electrocatalysis and propose innovative approaches for optimizing HER through chirality.展开更多
Aluminum alloys manufactured using traditional processes are increasingly unable to meet the high flexibility and performance requirements of modern engineering.In this study,Al-Mg-Sc-Zr alloys were manufactured via l...Aluminum alloys manufactured using traditional processes are increasingly unable to meet the high flexibility and performance requirements of modern engineering.In this study,Al-Mg-Sc-Zr alloys were manufactured via laser powder bed fusion(LPBF)to obtain high-performance aluminum alloys.To this end,process parameter optimization and heat treatment were adopted.The optimal process parameters were determined by initially analyzing the relative density and defect distribution under varying energy densities.The sample obtained under the optimal process parameters exhibited a relative density of 99.84%.Subsequently,the corresponding phase compositions,microstructures,and mechanical performance of the as-fabricated specimens were determined using the optimal process parameters before and after heat treatment.The microstructures of the samples showed typical equiaxed columnar bimodal grain structures,with Al_(3)(Sc,Zr)precipitates detected.The samples exhibited no significant anisotropy before and after heat treatment,while the grain orientation differences were dominated by high-angle grain boundaries.The mechanical properties of all the samples were characterized using tensile and hardness tests.The yield strength,ultimate tensile strength,and elongation of the sample were 475.0 MPa,508.2 MPa,and 8.3%,respectively.Overall,samples with high density,low porosity,high strength,and high plasticity were obtained by process parameter optimization and appropriate heat treatment.展开更多
Oxygen vacancies have been widely concerned with the facilitation effects of CO_(2)activation for CO_(2)methanation.However,little attention has been paid to the generation of active intermediate species induced by en...Oxygen vacancies have been widely concerned with the facilitation effects of CO_(2)activation for CO_(2)methanation.However,little attention has been paid to the generation of active intermediate species induced by enriched oxygen vacancies.Herein,we discovered that CeNiO_(3−δ)catalyst enriched oxygen vacancies can efficiently activate CO_(2)and realize high activity for photothermal CO_(2)methanation.In situ diffuse reflectance infrared Fourier transform spectroscopy(DRIFTS)proved that oxygen vacancies are beneficial to the formation of reactive intermediate species of polydentate carbonate over CeNiO_(3−δ),which is crucial for efficient CO_(2)methanation.These results revealed mechanistic insights into how effective CO_(2)activation induced by oxygen vacancies can be manipulated by adjusting the adsorption intermediate species.展开更多
microRNA 160(miR160),targeting auxin response factors(ARFs),plays many roles in plant development.We investigated the role of the mi R160/ARF axis in regulation of cotton seed size.Suppressing mi R160 activity,specifi...microRNA 160(miR160),targeting auxin response factors(ARFs),plays many roles in plant development.We investigated the role of the mi R160/ARF axis in regulation of cotton seed size.Suppressing mi R160 activity,specifically in the seed coat,led to smaller seeds and less fiber production owing to attenuated growth of the maternal integument.Scanning electron microscopy and histology showed that expansion of cells in the integument was retarded in mi R160-suppressed lines.Four Gh ARF genes were targeted by mi R160 and were upregulated in mi R160-suppressed lines,indicating that a mi R160/ARF axis is present in cotton.Five genes(Ghir_A05 G003740,Scaffold1878 G000010,Ghir_D09 G024980,Ghir_A11 G010730,and Ghir_A05 G041590),associated with reduced seed development were downregulated in mi R160-suppressed lines.Our results suggest that the mi R160/ARF axis controls maternal integument growth to influence seed size by directly or indirectly regulating seed development-associated genes.展开更多
Ni-Cr-Co-W superalloy(GH4099)can be used to manufacture high-temperature structural components of aero-engine combustion chambers for long-term service below 900℃.This study provides a comprehensive evaluation of the...Ni-Cr-Co-W superalloy(GH4099)can be used to manufacture high-temperature structural components of aero-engine combustion chambers for long-term service below 900℃.This study provides a comprehensive evaluation of the GH4099 superalloy fabricated using the laser powder bed fusion(LPBF)technique,focusing on the opti-mization of processing parameters and a systematic investigation of the microstructural evolution and mechanical properties of the as-deposited and heat-treated samples.An optimal parameter combination was established using the response surface method(RSM)design and the variance method.The as-deposited GH4099 alloy is primarily composed of columnar crystals grown epitaxially and M_(23)C_(6)carbides without the generation of theγ′-phase.After solution treatment,recrystallization and grain growth occurred,with the alloy remaining as large,irregu-larly shaped polygonal columnar crystals.The aging process precipitated substantial′-phase,which internally existed as a mixture of equiaxed and columnar crystals.LPBF-GH4099 superalloy exhibited a maximum room-temperature tensile strength of 1137.80 MPa and a high-temperature tensile strength of 780 MPa at 800◦C.Various strengthening mechanisms were observed in the as-deposited and heat-treated samples.The most sig-nificant grain boundary strengthening effect was observed in the deposit state,while solution strengthening was primarily due to the segregation of elements,such as Mo,W,and Cr,in thematrix.Precipitation strengthening,predominantly due to the′-phase,emerged as the main strengthening mechanism for the GH4099 superalloy post-aging treatment.This study presents significant insights into the LPBF-GH4099 alloy and provides a solid foundation for future studies and practical applications in this field.展开更多
Rare earth co-permeation of （NH4）3[CrMo6O24H6]·7H2O was reported and the conductivity of （NH4）3[CrMo6O24H6] was improved by 6.734×10^9 times. X-ray fluorescence spectrometry （XRF）, thermogravimetry-dif...Rare earth co-permeation of （NH4）3[CrMo6O24H6]·7H2O was reported and the conductivity of （NH4）3[CrMo6O24H6] was improved by 6.734×10^9 times. X-ray fluorescence spectrometry （XRF）, thermogravimetry-differential thermal analysis （TG-DTA）, X-ray diffraction （XRD） have been used to character （NH4）3[CrMo6O24H6]·7H2O and permeated sample. Experimental results showed that Nd could be permeated into the body of this sample and the XRD patterns showed great difference between （NH4）3[CrMo6O24H6]·7H2O and permeated sample. The structure of （NH4）3[CrMo6O24H6]·7H2O was destroyed and new compound MoN perhaps formed.展开更多
A plastic deformation zone near a screw dislocation is treated as an equivalent transformation inclusion by means of the Eshelby inclusion theory. A closed form solution for determining the interaction between a screw...A plastic deformation zone near a screw dislocation is treated as an equivalent transformation inclusion by means of the Eshelby inclusion theory. A closed form solution for determining the interaction between a screw dislocation and a plastically deformed zone of an arbitrary shape is obtained by using the solution between a dislocation and an equivalent transformation inclusion.展开更多
A novel coated urea(MVCU)was prepared,and its application effect was verified by field trials of oilseed rape in three main cultivation areas.Meanwhile,the nutrient release and coating layer changes of MVCU in static ...A novel coated urea(MVCU)was prepared,and its application effect was verified by field trials of oilseed rape in three main cultivation areas.Meanwhile,the nutrient release and coating layer changes of MVCU in static water at 25C and different soils were systematically evaluated.MVCU showed a long nutrient release time under static water(77 days)and soil incubation(140 days)conditions due to the slow degradation of the coating layer in MVCU,and its nitrogen release coincided well with oilseed rape nitrogen demand.The above results were further confirmed by FT-IR spectra and SEM analysis.Compared with conventional urea(U),the field trials of MVCU in the three main cultivation areas showed high nitrogen utilization efficiency and yield advantages in oilseed rape.The field trials results indicated that the MVCU significantly enhanced the aboveground dry matter(28.7%),the seed nitrogen concentration(9.5%)and aboveground nitrogen accumulation(42.5%)of oilseed rape at the mature stage as compared to that of the U.The oilseed rape yield enhanced by 932.8 kg/hm^(2),the average growth rate was 65.1%,and nitrogen utilization efficiency increased by 21.2%.In short,MVCU has the advantages of excellent slow-release performance and strong applicability,and its yield-increasing effect on oilseed rape could reach or even be better than that of traditional fertilization.展开更多
Non-peptide macrocyclic drugs possess unique structural advantages that allow them to target various biomolecules of interest and thus show therapeutic potential against various diseases such as cancer,infectious dise...Non-peptide macrocyclic drugs possess unique structural advantages that allow them to target various biomolecules of interest and thus show therapeutic potential against various diseases such as cancer,infectious diseases,etc.This review article examines 34 non-peptide macrocyclic drugs approved between 2000 and 2024,with a particular focus on the optimization process of representative macrocyclic drugs such as natural macrocycles,natural product-inspired macrocycles,and de novo-designed macrocycles.We discuss their structural characteristics,highlighting how conformational rigidity and enhanced target specificity contribute to their efficacy.Design details of these new macrocyclic drugs are illustrated through successful examples,offering insights for optimizing macrocycles.Of note,macrocyclization of U-shaped lead structures represents a novel molecular skeleton editing strategy in de novo macrocycle drug design.展开更多
To the Editor:Hemorrhagic shock is a critical pathological process characterized by microcirculation dysfunction and hypoperfusion,with severe consequences of cell damage and organ dysfunction.Intestinal barrier dysfu...To the Editor:Hemorrhagic shock is a critical pathological process characterized by microcirculation dysfunction and hypoperfusion,with severe consequences of cell damage and organ dysfunction.Intestinal barrier dysfunction is a critical link of distant organ injury caused by hemorrhagic shock.Prophylactic treatment with stellate ganglion block(SGB)significantly reduces hemorrhagic shock-induced intestinal barrier damage.展开更多
Silicon carbide(SiC)is widely used to improve the non-linear conductivity of non-linear resistive field grading composite.In this paper,the SiC nanoparticles are modified into core-shell nanoparticles with silica(SiO_...Silicon carbide(SiC)is widely used to improve the non-linear conductivity of non-linear resistive field grading composite.In this paper,the SiC nanoparticles are modified into core-shell nanoparticles with silica(SiO_(2))coating on the surface and are characterised by transmission electron microscopy and X-ray diffraction,respectively.The 7 wt%SiC@SiO_(2)/epoxy nanocomposite is then prepared,and the pure epoxy and 7 wt%SiC/epoxy nanocomposite are prepared as a contrast.The relative permittivity,thermally stimulated current,conductivity and breakdown strength are studied,respectively.The presence of SiO_(2)shell around SiC nanoparticles has a great effect on the relative permittivity and trap distribution.The epoxy nanocomposites show non-linear conductivity characteristics,compared with pure epoxy.The 7 wt%SiC@SiO_(2)/epoxy nanocomposite has higher switching electric field and breakdown strength than the 7 wt%SiC/epoxy nanocomposite,which is helpful for the application of non-linear resistive field grading composite in higher-voltage equipment or components.展开更多
基金supported in part by the National Natural Science Foundation of China,Nos.81927804(to GL),82260456(to LY),U21A20479(to LY)Science and Technology Planning Project of Shenzhen,No.JCYJ20230807140559047(to LY)+3 种基金Key-Area Research and Development Program of Guangdong Province,No.2020B0909020004(to GL)Guangdong Basic and Applied Research Foundation,No.2023A1515011478(to LY)the Science and Technology Program of Guangdong Province,No.2022A0505090007(to GL)Ministry of Science and Technology,Shenzhen,No.QN2022032013L(to LY)。
文摘Neural machine interface technology is a pioneering approach that aims to address the complex challenges of neurological dysfunctions and disabilities resulting from conditions such as congenital disorders,traumatic injuries,and neurological diseases.Neural machine interface technology establishes direct connections with the brain or peripheral nervous system to restore impaired motor,sensory,and cognitive functions,significantly improving patients'quality of life.This review analyzes the chronological development and integration of various neural machine interface technologies,including regenerative peripheral nerve interfaces,targeted muscle and sensory reinnervation,agonist–antagonist myoneural interfaces,and brain–machine interfaces.Recent advancements in flexible electronics and bioengineering have led to the development of more biocompatible and highresolution electrodes,which enhance the performance and longevity of neural machine interface technology.However,significant challenges remain,such as signal interference,fibrous tissue encapsulation,and the need for precise anatomical localization and reconstruction.The integration of advanced signal processing algorithms,particularly those utilizing artificial intelligence and machine learning,has the potential to improve the accuracy and reliability of neural signal interpretation,which will make neural machine interface technologies more intuitive and effective.These technologies have broad,impactful clinical applications,ranging from motor restoration and sensory feedback in prosthetics to neurological disorder treatment and neurorehabilitation.This review suggests that multidisciplinary collaboration will play a critical role in advancing neural machine interface technologies by combining insights from biomedical engineering,clinical surgery,and neuroengineering to develop more sophisticated and reliable interfaces.By addressing existing limitations and exploring new technological frontiers,neural machine interface technologies have the potential to revolutionize neuroprosthetics and neurorehabilitation,promising enhanced mobility,independence,and quality of life for individuals with neurological impairments.By leveraging detailed anatomical knowledge and integrating cutting-edge neuroengineering principles,researchers and clinicians can push the boundaries of what is possible and create increasingly sophisticated and long-lasting prosthetic devices that provide sustained benefits for users.
基金financially supported by National Natural Science Foundation of China (No.U1937601)the Industrial Technology Development Program of China(No.JCKY 2020203B019).
文摘One of the most widely used and well-established atomic oxygen(AO)protection solutions for low Earth orbit(LEO)satellites is the deposition of protective coatings on polymeric materials.However,manufacturing extensive expanses of these coating materials with good transparency,flexibility,smoothness,ultra-thinness,and exceptional AO resistance remains a critical issue.Herein,we successfully deposited a 400 nm thick polyorgansiloxane(SiO_(x)C_(y)H_(z))coating with high optical transparency and uniform good adherence on to a 1.2 m wide polyimide surface,by optimizing the distribution of hexamethyldisiloxane and oxygen as precursors in the roll-to-roll compatible plasmaenhanced chemical vapor deposition process.After AO irradiation with the fluence of 7.9×10^(20)atoms·cm^(–2),the erosion yield of the SiO_(x)C_(y)H_(z)-coated Kapton was less than 2.30×10^(–26)cm^3·atom^(–1),which was less than 0.77%of that of the Kapton.It indicates that the SiO_(x)C_(y)H_(z)coating can well prevent the erosion of Kapton by AO.In addition,it was also clarified that a SiO_(2) passivation layer was formed on the surface of the SiO_(x)C_(y)H_(z)coating during AO irradiation,which exhibited a‘self-reinforcing’defense mechanism.The entire preparation process of the SiO_(x)C_(y)H_(z)coating was highly efficient and low-cost,and it has shown great potential for applications in LEO.
基金supported by National Key Research and Development Program of China(2022YFF1001400)the National Natural Science Foundation of China(31830062 and 32172071)+1 种基金Innovation and Application of Superior Crop Germplasm Resources of Shihezi(2021NY01)Breeding of New Cotton Varieties and Application of Transgenic Breeding Technology(2022NY01)。
文摘Cotton fiber is one of the main raw materials for the textile industry.In recent years,many cotton fiber quality QTL have been identified,but few were applied in breeding.In this study,a genome wide association study(GWAS)of fiber-quality traits in 265 upland cotton breeding intermediate lines(GhBreeding),combined with genome-wide selective sweep analysis(GSSA)and genomic selection(GS),revealed 25 QTL.Most of these QTL were ignored by only using GWAS.The CRISPR/Cas9 mutants of GhMYB_D13 had shorter fiber,which indicates the credibility of QTL to a certain extent.Then these QTL were verified in other cotton natural populations,5 stable QTL were found having broad potential for application in breeding.Additionally,among these 5 stable QTL,superior genotypes of 4 showed an enrichment in most improved new varieties widely cultivated currently.These findings provide insights for how to identify more QTL through combined multiple genomic analysis to apply in breeding.
基金financially supported by the Key R&D Project of Hebei Province (No. 21282602Z)Shandong Province (No. 2020CXGC010506)the Innovative Group Project (No. 21621004)。
文摘Isostructural multicomponent crystals provide a promising way for fine-tuning physicochemical properties, whereas their design remains quite challenging. The purpose of this work was to provide a new strategy for obtaining isostructural multicomponent crystals by introducing coformers with functional group positional isomerism. Five isostructural salts of an antitumor drug dimethylaminomicheliolide(DMAMCL) were reported and designed with a series of dihydroxybenzoic acid regioisomers for the first time, which were identified by power and single-crystal X-ray diffractions. Similar lattice parameters suggested these obtained salts may have the same crystal packing mode. The quantitative similarity parameters via XPac, Crystal CMP and Mercury program further proved these crystal structures are3D isostructural. Hirshfeld surface maps and 2D fingerprint plots show that the isostructural salts have similar intermolecular interactions. Compared with DMAMCL, obvious improvement was observed in the thermal stability, hygroscopicity, and solubility of these isostructural salts. Meanwhile, isostructural crystals may have different physicochemical properties, even though the shape and molecular size are similar and the packing of crystal structures is equally matched.
基金financially supported by the National Natural Science Foundation of China(Nos.22178254 and 21621004)。
文摘The co-crystallization of quercetin(Qur)with a flexible molecule 4-(4-pyridinyldisulfanyl)pyridine(DPDS)in different solvents and conditions was investigated,yielded five multi-component crystalline phases and characterized with X-ray diffractions and thermal analysis.Although the crystal system of Qur-DPDSMe OH and Qur-DPDS-Dioxane is the same,the desolvation results revealed that Qur-DPDS-Me OH transformed to Qur-DPDS when Me OH solvent molecules escape from the lattice,while Qur-DPDS-Dioxane transformed to Qur-DPDS-II through a similar process,which is same with Qur-DPDS-THF.These two cocrystal polymorphs Qur-DPDS and Qur-DPDS-II obey an enantiotropic relationship.Moreover,the formation of cocrystal solvates improves the packing efficiency of crystals.Crystal structure analysis showed that hydrogen bonds and conformations of the corresponding parent molecules play a major role in molecular assembly and crystal packing patterns,thus bring different physicochemical properties.Finally,the fluorescence spectra and quantum-chemical calculations were carried out to explore the difference in the optical-physical properties.
基金the full support of the National Natural Science Foundation of China(62071154,51272052 and50902040)the Natural Science Foundation of Heilongjiang Province of China(LH2020B011 and LH2019B006)the Scientific Research Projects of Basic Scientific Research Operational Expenses of Heilongjiang Provincial Colleges and Universities(2021-KYYWF-0171)。
文摘The integration of machine learning and electrocatalysis presents nota ble advancements in designing and predicting the performance of chiral materials for hydrogen evolution reactions(HER).This study utilizes theoretical calculations and machine learning techniques to assess the HER performance of both chiral and achiral M-N-SWCNTs(M=In,Bi,and Sb)single-atom catalysts(SACs).The stability preferences of metal atoms are dependent on chirality when interacting with chiral SWCNTs.The HER activity of the right-handed In-N-SWCNT is 5.71 times greater than its achiral counterpart,whereas the left-handed In-N-SWCNT exhibits a 5.12-fold enhancement.The calculated hydrogen adsorption free energy for the right-handed In-N-SWCNT reaches as low as-0.02 eV.This enhancement is attributed to the symmetry breaking in spin density distribution,transitioning from C_(2V)in achiral SACs to C_(2)in chiral SACs,which facilitates active site transfer and enhances local spin density.Right-handed M-N-SWCNTs exhibit superiorα-electron separation and transport efficiency relative to left-handed variants,owing to the chiral induced spin selectivity(CISS)effect,with spin-upα-electron density reaching 3.43×10^(-3)e/Bohr^(3)at active sites.Machine learning provides deeper insights,revealing that the interplay of weak spatial electronic effects and appropriate curvature-chirality effects significantly enhances HER performance.A weaker spatial electronic effect correlates with higher HER activity,larger exchange current density,and higher turnover frequency.The curvature-chirality effect undersco res the influence of intrinsic structures on HER performance.These findings offer critical insights into the role of chirality in electrocatalysis and propose innovative approaches for optimizing HER through chirality.
基金supported by National Natural Science Foundation of China(Grant Nos.5233500651975073)State Key Laboratory of Mechanical Transmission for Advanced Equipment(Grant No.SKLMT-MSKFKT-202104).
文摘Aluminum alloys manufactured using traditional processes are increasingly unable to meet the high flexibility and performance requirements of modern engineering.In this study,Al-Mg-Sc-Zr alloys were manufactured via laser powder bed fusion(LPBF)to obtain high-performance aluminum alloys.To this end,process parameter optimization and heat treatment were adopted.The optimal process parameters were determined by initially analyzing the relative density and defect distribution under varying energy densities.The sample obtained under the optimal process parameters exhibited a relative density of 99.84%.Subsequently,the corresponding phase compositions,microstructures,and mechanical performance of the as-fabricated specimens were determined using the optimal process parameters before and after heat treatment.The microstructures of the samples showed typical equiaxed columnar bimodal grain structures,with Al_(3)(Sc,Zr)precipitates detected.The samples exhibited no significant anisotropy before and after heat treatment,while the grain orientation differences were dominated by high-angle grain boundaries.The mechanical properties of all the samples were characterized using tensile and hardness tests.The yield strength,ultimate tensile strength,and elongation of the sample were 475.0 MPa,508.2 MPa,and 8.3%,respectively.Overall,samples with high density,low porosity,high strength,and high plasticity were obtained by process parameter optimization and appropriate heat treatment.
基金This work was supported in part by the Foundation of Guangdong Educational Committee （2014KTSCX191） and the National Natural Science Foundation of China （61201087）.
基金Financial support from the National Natural Science Foundation of China(Nos.22025202,51572191,and 21633004)the Jiangsu Funding Program for Excellent Postdoctoral Talent is gratefully acknowledged.
文摘Oxygen vacancies have been widely concerned with the facilitation effects of CO_(2)activation for CO_(2)methanation.However,little attention has been paid to the generation of active intermediate species induced by enriched oxygen vacancies.Herein,we discovered that CeNiO_(3−δ)catalyst enriched oxygen vacancies can efficiently activate CO_(2)and realize high activity for photothermal CO_(2)methanation.In situ diffuse reflectance infrared Fourier transform spectroscopy(DRIFTS)proved that oxygen vacancies are beneficial to the formation of reactive intermediate species of polydentate carbonate over CeNiO_(3−δ),which is crucial for efficient CO_(2)methanation.These results revealed mechanistic insights into how effective CO_(2)activation induced by oxygen vacancies can be manipulated by adjusting the adsorption intermediate species.
基金supported by the National Transgenic Plant Research of China(2016ZX0800-00-004)。
文摘microRNA 160(miR160),targeting auxin response factors(ARFs),plays many roles in plant development.We investigated the role of the mi R160/ARF axis in regulation of cotton seed size.Suppressing mi R160 activity,specifically in the seed coat,led to smaller seeds and less fiber production owing to attenuated growth of the maternal integument.Scanning electron microscopy and histology showed that expansion of cells in the integument was retarded in mi R160-suppressed lines.Four Gh ARF genes were targeted by mi R160 and were upregulated in mi R160-suppressed lines,indicating that a mi R160/ARF axis is present in cotton.Five genes(Ghir_A05 G003740,Scaffold1878 G000010,Ghir_D09 G024980,Ghir_A11 G010730,and Ghir_A05 G041590),associated with reduced seed development were downregulated in mi R160-suppressed lines.Our results suggest that the mi R160/ARF axis controls maternal integument growth to influence seed size by directly or indirectly regulating seed development-associated genes.
基金supported by National Natural Science Foundation of China(Grant Nos.51975073,52335006,52201105)Natural Science Foundation of Chongqing China(Grant No.CSTB2022NSCQ-MSX0992)+2 种基金Innovation Support Program for Overseas Returnees in Chongqing China(Grant No.cx2023061)State Key Laboratory of Mechanical Trans-mission for Advanced Equipment of China(Grant No.SKLMT-MSKFKT-202104)The authors gratefully acknowledge all the researchers and laboratories for providing the experimental facilities.
文摘Ni-Cr-Co-W superalloy(GH4099)can be used to manufacture high-temperature structural components of aero-engine combustion chambers for long-term service below 900℃.This study provides a comprehensive evaluation of the GH4099 superalloy fabricated using the laser powder bed fusion(LPBF)technique,focusing on the opti-mization of processing parameters and a systematic investigation of the microstructural evolution and mechanical properties of the as-deposited and heat-treated samples.An optimal parameter combination was established using the response surface method(RSM)design and the variance method.The as-deposited GH4099 alloy is primarily composed of columnar crystals grown epitaxially and M_(23)C_(6)carbides without the generation of theγ′-phase.After solution treatment,recrystallization and grain growth occurred,with the alloy remaining as large,irregu-larly shaped polygonal columnar crystals.The aging process precipitated substantial′-phase,which internally existed as a mixture of equiaxed and columnar crystals.LPBF-GH4099 superalloy exhibited a maximum room-temperature tensile strength of 1137.80 MPa and a high-temperature tensile strength of 780 MPa at 800◦C.Various strengthening mechanisms were observed in the as-deposited and heat-treated samples.The most sig-nificant grain boundary strengthening effect was observed in the deposit state,while solution strengthening was primarily due to the segregation of elements,such as Mo,W,and Cr,in thematrix.Precipitation strengthening,predominantly due to the′-phase,emerged as the main strengthening mechanism for the GH4099 superalloy post-aging treatment.This study presents significant insights into the LPBF-GH4099 alloy and provides a solid foundation for future studies and practical applications in this field.
基金the Key Science and Technology Foundation of Heilongjiang Province(Grant No.GB02A301) National Natural Science Foundation of China(Grant No.2037101)
文摘Rare earth co-permeation of （NH4）3[CrMo6O24H6]·7H2O was reported and the conductivity of （NH4）3[CrMo6O24H6] was improved by 6.734×10^9 times. X-ray fluorescence spectrometry （XRF）, thermogravimetry-differential thermal analysis （TG-DTA）, X-ray diffraction （XRD） have been used to character （NH4）3[CrMo6O24H6]·7H2O and permeated sample. Experimental results showed that Nd could be permeated into the body of this sample and the XRD patterns showed great difference between （NH4）3[CrMo6O24H6]·7H2O and permeated sample. The structure of （NH4）3[CrMo6O24H6]·7H2O was destroyed and new compound MoN perhaps formed.
基金Project supported by the National Basic Research Program of China (No.2004CB619303)the National Science Foundation of China (No.10572088).
文摘A plastic deformation zone near a screw dislocation is treated as an equivalent transformation inclusion by means of the Eshelby inclusion theory. A closed form solution for determining the interaction between a screw dislocation and a plastically deformed zone of an arbitrary shape is obtained by using the solution between a dislocation and an equivalent transformation inclusion.
基金financial support was provided by the National Key R&D Program of China(2018YFD0200901).
文摘A novel coated urea(MVCU)was prepared,and its application effect was verified by field trials of oilseed rape in three main cultivation areas.Meanwhile,the nutrient release and coating layer changes of MVCU in static water at 25C and different soils were systematically evaluated.MVCU showed a long nutrient release time under static water(77 days)and soil incubation(140 days)conditions due to the slow degradation of the coating layer in MVCU,and its nitrogen release coincided well with oilseed rape nitrogen demand.The above results were further confirmed by FT-IR spectra and SEM analysis.Compared with conventional urea(U),the field trials of MVCU in the three main cultivation areas showed high nitrogen utilization efficiency and yield advantages in oilseed rape.The field trials results indicated that the MVCU significantly enhanced the aboveground dry matter(28.7%),the seed nitrogen concentration(9.5%)and aboveground nitrogen accumulation(42.5%)of oilseed rape at the mature stage as compared to that of the U.The oilseed rape yield enhanced by 932.8 kg/hm^(2),the average growth rate was 65.1%,and nitrogen utilization efficiency increased by 21.2%.In short,MVCU has the advantages of excellent slow-release performance and strong applicability,and its yield-increasing effect on oilseed rape could reach or even be better than that of traditional fertilization.
基金supported by the Noncommunicable Chronic Diseases-National Science and Technology Major Project(No.2023ZD0507700,China)National Natural Science Foundation of China(No.22277110 and 82473761)+2 种基金Joint Research Fund of Science and Technology R&D Plan of Henan Province(No.222301420068,China)Natural Science Foundation of Henan Province(No.242301420005 and 252300421243,China)Key Research Project for Basic Research in Henan Province Universities(No.25ZX001,China).
文摘Non-peptide macrocyclic drugs possess unique structural advantages that allow them to target various biomolecules of interest and thus show therapeutic potential against various diseases such as cancer,infectious diseases,etc.This review article examines 34 non-peptide macrocyclic drugs approved between 2000 and 2024,with a particular focus on the optimization process of representative macrocyclic drugs such as natural macrocycles,natural product-inspired macrocycles,and de novo-designed macrocycles.We discuss their structural characteristics,highlighting how conformational rigidity and enhanced target specificity contribute to their efficacy.Design details of these new macrocyclic drugs are illustrated through successful examples,offering insights for optimizing macrocycles.Of note,macrocyclization of U-shaped lead structures represents a novel molecular skeleton editing strategy in de novo macrocycle drug design.
基金National Natural Science Foundation of China to Chunyu Niu(No.81770492)Natural Science Foundation of Hebei Province to Zigang Zhao(No.H2020405012)。
文摘To the Editor:Hemorrhagic shock is a critical pathological process characterized by microcirculation dysfunction and hypoperfusion,with severe consequences of cell damage and organ dysfunction.Intestinal barrier dysfunction is a critical link of distant organ injury caused by hemorrhagic shock.Prophylactic treatment with stellate ganglion block(SGB)significantly reduces hemorrhagic shock-induced intestinal barrier damage.
基金National Key R&D Program of China,Grant/Award Number:2018YFE0200100National Natural Science Foundation of China,Grant/Award Number:52007043Natural Science Foundation of Heilongjiang Province,Grant/Award Number:TD2019E002。
文摘Silicon carbide(SiC)is widely used to improve the non-linear conductivity of non-linear resistive field grading composite.In this paper,the SiC nanoparticles are modified into core-shell nanoparticles with silica(SiO_(2))coating on the surface and are characterised by transmission electron microscopy and X-ray diffraction,respectively.The 7 wt%SiC@SiO_(2)/epoxy nanocomposite is then prepared,and the pure epoxy and 7 wt%SiC/epoxy nanocomposite are prepared as a contrast.The relative permittivity,thermally stimulated current,conductivity and breakdown strength are studied,respectively.The presence of SiO_(2)shell around SiC nanoparticles has a great effect on the relative permittivity and trap distribution.The epoxy nanocomposites show non-linear conductivity characteristics,compared with pure epoxy.The 7 wt%SiC@SiO_(2)/epoxy nanocomposite has higher switching electric field and breakdown strength than the 7 wt%SiC/epoxy nanocomposite,which is helpful for the application of non-linear resistive field grading composite in higher-voltage equipment or components.
