Stress tolerance plays a vital role in ensuring the effectiveness of piezoresistive sensing films used in flexible pressure sensors.However,existing methods for enhancing stress tolerance employ dome-shaped,wrinkle-sh...Stress tolerance plays a vital role in ensuring the effectiveness of piezoresistive sensing films used in flexible pressure sensors.However,existing methods for enhancing stress tolerance employ dome-shaped,wrinkle-shaped,and pyramidal-shaped microstructures in intricate molding and demolding processes,which introduce significant fabrication challenges and limit the sensing performance.To address these shortcomings,this paper presents periodic microslits in a sensing film made of multiwalled carbon nanotubes and polydimethylsiloxane to realize ultrahigh stress tolerance with a theoretical maximum of 2.477 MPa and a sensitivity of 18.092 kPa−1.The periodic microslits permit extensive deformation under high pressure(e.g.,400 kPa)to widen the detection range.Moreover,the periodic microslits also enhance the sensitivity based on simultaneously exhibiting multiple synapses within the sensing interface and between the periodic sensing cells.The proposed solution is verified by experiments using sensors based on the microslit strategy for wind direction detection,robot movement sensing,and human health monitoring.In these experiments,vehicle load detection is achieved for ultrahigh pressure sensing under an ultrahigh pressure of over 400 kPa and a ratio of the contact area to the total area of 32.74%.The results indicate that the proposed microslit strategy can achieve ultrahigh stress tolerance while simplifying the fabrication complexity of preparing microstructure sensing films.展开更多
The extraction of uranium (U) from U-bearing wastewater is of paramount importance for mitigating negative environmental impacts and recovering U resources. Microbial reduction of soluble hexavalent uranium (U(VI)) to...The extraction of uranium (U) from U-bearing wastewater is of paramount importance for mitigating negative environmental impacts and recovering U resources. Microbial reduction of soluble hexavalent uranium (U(VI)) to insoluble tetravalent uranium (U(IV)) holds immense potential for this purpose, but its practical application has been impeded by the challenges associated with managing U-bacterial mixtures and the biotoxicity of U. To address these challenges, we present a novel spontaneous microbial electrochemical (SMEC) method that spatially decoupled the microbial oxidation reaction and the U(VI) reduction reaction. Our results demonstrated stable and efficient U extraction with net electrical energy production, which was achieved with both synthetic and real wastewater. U(VI) removal occurred via diffusion-controlled U(VI)-to-U(IV) reduction-precipitation at the cathode, and the UIVO_(2) deposited on the surface of the cathode contributed to the stability and durability of the abiotic U(VI) reduction. Metagenomic sequencing revealed the formation of efficient electroactive communities on the anodic biofilm and enrichment of the key functional genes and metabolic pathways involved in electron transfer, energy metabolism, the TCA cycle, and acetate metabolism, which indicated the ectopic reduction of U(VI) at the cathode. Our study represents a significant advancement in the cost-effective recovery of U from U(VI)-bearing wastewater and may open a new avenue for sustainable uranium extraction.展开更多
Tandem catalysis,capable of decoupling individual steps,provides a feasible way to build a high-efficiency CO_(2) electro-conversion system for multicarbons(C_(2+)).The construction of electrocatalytic materials is on...Tandem catalysis,capable of decoupling individual steps,provides a feasible way to build a high-efficiency CO_(2) electro-conversion system for multicarbons(C_(2+)).The construction of electrocatalytic materials is one of focusing issues.Herein,we fabricated a single atom involved multivalent oxide-derived Cu composite material and found it inclined to reconstruct into oxygen-deficient multiphase Cu based species hybridized with monatomic Ni on N doped C matrix.In this prototype,rapid CO generation and C-C coupling are successively achieved on NiN4 sites and surface amorphized Cu species with defects,resembling a micro-production line.In this way,the in situ formed tandem catalyst exhibited a high Faradaic efficiency(FE)of~78%for C_(2+)products along with satisfactory durability over 50 h.Particularly,the reconstruction-induced amorphous layer with abundant asymmetric sites should be favorable to improve the ethanol selectivity(FE:63%),which is about 10 times higher than that of the non-tandem Cu-based contrast material.This work offers a new approach for manipulating tandem catalyst systems towards enhancing C_(2+)products.展开更多
Mode splitters that directly separate modes without changing their orders are highly promising to improve the flexibility of the mode-division multiplexing systems.In this paper,we design a high-performance mode split...Mode splitters that directly separate modes without changing their orders are highly promising to improve the flexibility of the mode-division multiplexing systems.In this paper,we design a high-performance mode splitter on the silicon-oninsulator platform with a compact footprint of 14μm×2.5μm using an inverse design method based on shape optimization.The fabrication of this mode splitter requires only a single lithography step and exhibits good fabrication tolerances.The experimental results show that the proposed device exhibits state-of-the-art insertion loss(<0.9 dB)and cross talk(<-16 dB)over a broad bandwidth(1500-1600 nm).Furthermore,the shape optimization method used is implemented to design a dual-mode(de)multiplexer,and the experimental results fulfill the design objective,demonstrating the excellent generality of the design method in this paper.展开更多
The ultimate purpose of phytoextraction is not only to remove heavy metals from soil but also to improve soil quality.Here, we evaluated how the joint effect of Streptomyces pactum(strain Act12) and inorganic(Hoagland...The ultimate purpose of phytoextraction is not only to remove heavy metals from soil but also to improve soil quality.Here, we evaluated how the joint effect of Streptomyces pactum(strain Act12) and inorganic(Hoagland’s solution) and organic(humic acid and peat) nutrients affected the phytoextraction practice of cadmium(Cd) and zinc(Zn) by potherb mustard, and the microbial community composition within rhizosphere was also investigated.The results indicated that the nutrients exerted synergistically with Act12, all increasing the plant biomass and Cd/Zn uptakes.The inoculation of Act12 alone significantly increased dehydrogenase activity of rhizosphere soil(P<0.05), while urease and alkaline phosphatase activities varied in different dosage of Act12.Combined application of microbial strain with nutrients increased enzymatic activities with the elevated dosage of Act12.16S ribosomal RNA high-throughput sequencing analysis revealed that Act12 inoculation reduced the diversity of rhizosphere bacteria.The Act12 and nutrients did not change dominant phyla i.e.,Proteobacteria, Bacteroidetes, Gemmatimonadetes, Actinobacteria and Acidobacteria, but their relative abundance differed among the treatments with: Peat>Act12>Humic acid >Hoagland’s solution.Comparatively, Sphingomonas replaced Thiobacillus as dominant genus after Act12 application.The increase in the Sphingomonas and Flavisolibacter abundances under Act12 and nutrients treatments gave rise to growth-promoting effect on plant.Our results revealed the important role for rhizosphere microbiota in mediating soil biochemical traits and plant growth, and our approach charted a path toward the development of Act12 combined with soil nutrients to enhance soil quality and phytoextraction efficiency in Cd/Zn-contaminated soils.展开更多
The internal force antagonism(IFA)problem is one of the most important issues limiting the applications and popularization of redundant parallel robots in industry.Redundant cable-driven parallel robots(RCDPRs)and red...The internal force antagonism(IFA)problem is one of the most important issues limiting the applications and popularization of redundant parallel robots in industry.Redundant cable-driven parallel robots(RCDPRs)and redundant rigid parallel robots(RRPRs)behave very differently in this problem.To clarify the essence of IFA,this study first analyzes the causes and influencing factors of IFA.Next,an evaluation index for IFA is proposed,and its calculating algorithm is developed.Then,three graphical analysis methods based on this index are proposed.Finally,the performance of RCDPRs and RRPRs in IFA under three configurations are analyzed.Results show that RRPRs produce IFA in nearly all the areas of the workspace,whereas RCDPRs produce IFA in only some areas of the workspace,and the IFA in RCDPRs is milder than that RRPRs.Thus,RCDPRs more fault-tolerant and easier to control and thus more conducive for industrial application and popularization than RRPRs.Furthermore,the proposed analysis methods can be used for the configuration optimization design of RCDPRs.展开更多
Poor electron conductivity is the key issue influencing the rate capability of NaTi_(2)(PO_(4))_(3)(NTP).Hence,herein,polyacrylonitrile(PAN)was utilized as a NTP modifier by simply mixing NTP in a liquid PAN suspensio...Poor electron conductivity is the key issue influencing the rate capability of NaTi_(2)(PO_(4))_(3)(NTP).Hence,herein,polyacrylonitrile(PAN)was utilized as a NTP modifier by simply mixing NTP in a liquid PAN suspension,followed by sintering at 850℃ for 5 h.The product with a PAN/NTP mass ratio of 0.3 delivered splendid rate capabilities(achieving lithiation capacities of 282.9,243.0,207.1,173.1,133.5,and 257.5 mAh g^(−1) at 0.1,0.2,0.4,0.8,1.6,and 0.1 A^(−1),respectively)and excellent long cycling life(capacity retention of 165.5 mAh g^(−1) after 1200 cycles at 0.5 A g−1).Based on detailed structural and compositional characterizations,as well as cyclic voltammetry(CV)and electrochemical impedance spectroscopy(EIS),the uniform N-doped carbon coating stemming from PAN carbonization around the NTP particles promoted electron transfer,while the oxygen vacancies induced by N-doping in NTP facilitated Li+diffusion.The boosted and well matched electronic and ionic conductivities give rise to the optimized electrochemical performance.展开更多
In current practice of bolt reaming and anchoring of roadways in soft coal and rock mass,resin cartridges bend easily under the strong pushing and stirring of bolts,and the resin accumulates in the bolt-reamed area an...In current practice of bolt reaming and anchoring of roadways in soft coal and rock mass,resin cartridges bend easily under the strong pushing and stirring of bolts,and the resin accumulates in the bolt-reamed area and does not participate in the stirring.As a result,bolts encounter high drilling resistance and cannot reach the bottom of drillholes.The effective anchorage length is far less than the actual anchorage length.Bolts are not centered,and the shear is misaligned at the joint surface in the reaming area,which leads to cracking of the whole anchoring solid and large shear deformation of bolts.This study systematically analyzes the characteristics of roadway bolt reaming and anchoring.The influences of resin stirring force,bolt pull-out force,and reamingeanchoring solid strength on reamingeanchoring performance were analyzed theoretically.The main purpose is to develop a device that enhances reaming and anchoring.The mechanism through which the device strengthens the reamingeanchoring solid was analyzed theoretically.Numerical simulation and experiments were carried out to verify the improved performance of the small-pore reaming and anchoring using the proposed technology.The results showed that the stirring migration rate of the resin cartridge is greatly improved by adding the device to bolts.The reaction rate of the anchoring mixture,stirring pressure,pull-out force of the reaming and anchoring system,bolt concentricity,and shear and compressive strengths of the anchoring solid are also enhanced in the reaming area.This ensures that the resin cartridge in the reaming area is completely stirred,which greatly improves the shear resistance of the reamingeanchoring solid.Meanwhile,the drilling performance,torsional force,and stirring efficiency of bolts are maximized and prevail over those of conventional bolts.展开更多
We examined a 1514 nm eye-safe passively Q-switched self-optical parametric oscillator. The nonlinear crystal is an a-cut Nd:MgO:PPLN crystal, and the size of the crystal was 6 mm × 2 mm × 30 mm with 0.4 at....We examined a 1514 nm eye-safe passively Q-switched self-optical parametric oscillator. The nonlinear crystal is an a-cut Nd:MgO:PPLN crystal, and the size of the crystal was 6 mm × 2 mm × 30 mm with 0.4 at.%Nd^3+ doped and a grating period of 29.8 μm. When the crystal absorbed 12.8 W, the output maximum singlepulse energy reached 39 μJ, and a pulse width of 6.1 ns at a repetition rate of 5.4 kHz was obtained.The peak power was 6 kW, giving a slope efficiency of 42%.展开更多
基金supported by the National Key R&D Program of China(Grant No.2022YFB3204800).
文摘Stress tolerance plays a vital role in ensuring the effectiveness of piezoresistive sensing films used in flexible pressure sensors.However,existing methods for enhancing stress tolerance employ dome-shaped,wrinkle-shaped,and pyramidal-shaped microstructures in intricate molding and demolding processes,which introduce significant fabrication challenges and limit the sensing performance.To address these shortcomings,this paper presents periodic microslits in a sensing film made of multiwalled carbon nanotubes and polydimethylsiloxane to realize ultrahigh stress tolerance with a theoretical maximum of 2.477 MPa and a sensitivity of 18.092 kPa−1.The periodic microslits permit extensive deformation under high pressure(e.g.,400 kPa)to widen the detection range.Moreover,the periodic microslits also enhance the sensitivity based on simultaneously exhibiting multiple synapses within the sensing interface and between the periodic sensing cells.The proposed solution is verified by experiments using sensors based on the microslit strategy for wind direction detection,robot movement sensing,and human health monitoring.In these experiments,vehicle load detection is achieved for ultrahigh pressure sensing under an ultrahigh pressure of over 400 kPa and a ratio of the contact area to the total area of 32.74%.The results indicate that the proposed microslit strategy can achieve ultrahigh stress tolerance while simplifying the fabrication complexity of preparing microstructure sensing films.
基金supported by the National Natural Science Foundation of China(Nos.52200202 and 42077352).
文摘The extraction of uranium (U) from U-bearing wastewater is of paramount importance for mitigating negative environmental impacts and recovering U resources. Microbial reduction of soluble hexavalent uranium (U(VI)) to insoluble tetravalent uranium (U(IV)) holds immense potential for this purpose, but its practical application has been impeded by the challenges associated with managing U-bacterial mixtures and the biotoxicity of U. To address these challenges, we present a novel spontaneous microbial electrochemical (SMEC) method that spatially decoupled the microbial oxidation reaction and the U(VI) reduction reaction. Our results demonstrated stable and efficient U extraction with net electrical energy production, which was achieved with both synthetic and real wastewater. U(VI) removal occurred via diffusion-controlled U(VI)-to-U(IV) reduction-precipitation at the cathode, and the UIVO_(2) deposited on the surface of the cathode contributed to the stability and durability of the abiotic U(VI) reduction. Metagenomic sequencing revealed the formation of efficient electroactive communities on the anodic biofilm and enrichment of the key functional genes and metabolic pathways involved in electron transfer, energy metabolism, the TCA cycle, and acetate metabolism, which indicated the ectopic reduction of U(VI) at the cathode. Our study represents a significant advancement in the cost-effective recovery of U from U(VI)-bearing wastewater and may open a new avenue for sustainable uranium extraction.
基金supported by the National Natural Science Foundation of China(Nos.52302092,22375019)the Beijing Natural Science Foundation(No.2212018)+2 种基金the Beijing Institute of Technology Research Fund Program for Young Scholars(No.2022CX01011)the Fundamental Research Funds for the Central Universities(Nos.2023MS057 and JB 2022004)the Open Research Fund of State Environmental Protection Key Laboratory of Eco-industry,Chinese Research Academy of Environmental Sciences(No.2022KFF-07).
文摘Tandem catalysis,capable of decoupling individual steps,provides a feasible way to build a high-efficiency CO_(2) electro-conversion system for multicarbons(C_(2+)).The construction of electrocatalytic materials is one of focusing issues.Herein,we fabricated a single atom involved multivalent oxide-derived Cu composite material and found it inclined to reconstruct into oxygen-deficient multiphase Cu based species hybridized with monatomic Ni on N doped C matrix.In this prototype,rapid CO generation and C-C coupling are successively achieved on NiN4 sites and surface amorphized Cu species with defects,resembling a micro-production line.In this way,the in situ formed tandem catalyst exhibited a high Faradaic efficiency(FE)of~78%for C_(2+)products along with satisfactory durability over 50 h.Particularly,the reconstruction-induced amorphous layer with abundant asymmetric sites should be favorable to improve the ethanol selectivity(FE:63%),which is about 10 times higher than that of the non-tandem Cu-based contrast material.This work offers a new approach for manipulating tandem catalyst systems towards enhancing C_(2+)products.
基金supported by the National Natural Science Foundation of China(Nos.62105167,62075188,and 61974078)the Natural Science Foundation of Zhejiang Province(Nos.LQ22F050008 and LY21F050007)+1 种基金the Natural Science Foundation of Ningbo(Nos.2021J074 and 2021J059)the Key Research and Development Program of Jiangsu Province(No.BE2021082)。
文摘Mode splitters that directly separate modes without changing their orders are highly promising to improve the flexibility of the mode-division multiplexing systems.In this paper,we design a high-performance mode splitter on the silicon-oninsulator platform with a compact footprint of 14μm×2.5μm using an inverse design method based on shape optimization.The fabrication of this mode splitter requires only a single lithography step and exhibits good fabrication tolerances.The experimental results show that the proposed device exhibits state-of-the-art insertion loss(<0.9 dB)and cross talk(<-16 dB)over a broad bandwidth(1500-1600 nm).Furthermore,the shape optimization method used is implemented to design a dual-mode(de)multiplexer,and the experimental results fulfill the design objective,demonstrating the excellent generality of the design method in this paper.
基金supported by the Fundamental Research Funds for the Central Universities of China (Nos. 3102019JC007, G2021KY0601)。
文摘The ultimate purpose of phytoextraction is not only to remove heavy metals from soil but also to improve soil quality.Here, we evaluated how the joint effect of Streptomyces pactum(strain Act12) and inorganic(Hoagland’s solution) and organic(humic acid and peat) nutrients affected the phytoextraction practice of cadmium(Cd) and zinc(Zn) by potherb mustard, and the microbial community composition within rhizosphere was also investigated.The results indicated that the nutrients exerted synergistically with Act12, all increasing the plant biomass and Cd/Zn uptakes.The inoculation of Act12 alone significantly increased dehydrogenase activity of rhizosphere soil(P<0.05), while urease and alkaline phosphatase activities varied in different dosage of Act12.Combined application of microbial strain with nutrients increased enzymatic activities with the elevated dosage of Act12.16S ribosomal RNA high-throughput sequencing analysis revealed that Act12 inoculation reduced the diversity of rhizosphere bacteria.The Act12 and nutrients did not change dominant phyla i.e.,Proteobacteria, Bacteroidetes, Gemmatimonadetes, Actinobacteria and Acidobacteria, but their relative abundance differed among the treatments with: Peat>Act12>Humic acid >Hoagland’s solution.Comparatively, Sphingomonas replaced Thiobacillus as dominant genus after Act12 application.The increase in the Sphingomonas and Flavisolibacter abundances under Act12 and nutrients treatments gave rise to growth-promoting effect on plant.Our results revealed the important role for rhizosphere microbiota in mediating soil biochemical traits and plant growth, and our approach charted a path toward the development of Act12 combined with soil nutrients to enhance soil quality and phytoextraction efficiency in Cd/Zn-contaminated soils.
基金the financial support of the National Natural Science Foundation of China(Grant No.51975307).
文摘The internal force antagonism(IFA)problem is one of the most important issues limiting the applications and popularization of redundant parallel robots in industry.Redundant cable-driven parallel robots(RCDPRs)and redundant rigid parallel robots(RRPRs)behave very differently in this problem.To clarify the essence of IFA,this study first analyzes the causes and influencing factors of IFA.Next,an evaluation index for IFA is proposed,and its calculating algorithm is developed.Then,three graphical analysis methods based on this index are proposed.Finally,the performance of RCDPRs and RRPRs in IFA under three configurations are analyzed.Results show that RRPRs produce IFA in nearly all the areas of the workspace,whereas RCDPRs produce IFA in only some areas of the workspace,and the IFA in RCDPRs is milder than that RRPRs.Thus,RCDPRs more fault-tolerant and easier to control and thus more conducive for industrial application and popularization than RRPRs.Furthermore,the proposed analysis methods can be used for the configuration optimization design of RCDPRs.
基金This work was supported by Project ZR2022QE165 of Shandong Provincial Natural Science Foundation,China.
文摘Poor electron conductivity is the key issue influencing the rate capability of NaTi_(2)(PO_(4))_(3)(NTP).Hence,herein,polyacrylonitrile(PAN)was utilized as a NTP modifier by simply mixing NTP in a liquid PAN suspension,followed by sintering at 850℃ for 5 h.The product with a PAN/NTP mass ratio of 0.3 delivered splendid rate capabilities(achieving lithiation capacities of 282.9,243.0,207.1,173.1,133.5,and 257.5 mAh g^(−1) at 0.1,0.2,0.4,0.8,1.6,and 0.1 A^(−1),respectively)and excellent long cycling life(capacity retention of 165.5 mAh g^(−1) after 1200 cycles at 0.5 A g−1).Based on detailed structural and compositional characterizations,as well as cyclic voltammetry(CV)and electrochemical impedance spectroscopy(EIS),the uniform N-doped carbon coating stemming from PAN carbonization around the NTP particles promoted electron transfer,while the oxygen vacancies induced by N-doping in NTP facilitated Li+diffusion.The boosted and well matched electronic and ionic conductivities give rise to the optimized electrochemical performance.
基金supported by the National Natural Science Foundation of China-Liaoning Joint Fund Key Project(Grant No.U1908222)the National Natural Science Foundation of China Youth Science Fund(Grant No.52104087).
文摘In current practice of bolt reaming and anchoring of roadways in soft coal and rock mass,resin cartridges bend easily under the strong pushing and stirring of bolts,and the resin accumulates in the bolt-reamed area and does not participate in the stirring.As a result,bolts encounter high drilling resistance and cannot reach the bottom of drillholes.The effective anchorage length is far less than the actual anchorage length.Bolts are not centered,and the shear is misaligned at the joint surface in the reaming area,which leads to cracking of the whole anchoring solid and large shear deformation of bolts.This study systematically analyzes the characteristics of roadway bolt reaming and anchoring.The influences of resin stirring force,bolt pull-out force,and reamingeanchoring solid strength on reamingeanchoring performance were analyzed theoretically.The main purpose is to develop a device that enhances reaming and anchoring.The mechanism through which the device strengthens the reamingeanchoring solid was analyzed theoretically.Numerical simulation and experiments were carried out to verify the improved performance of the small-pore reaming and anchoring using the proposed technology.The results showed that the stirring migration rate of the resin cartridge is greatly improved by adding the device to bolts.The reaction rate of the anchoring mixture,stirring pressure,pull-out force of the reaming and anchoring system,bolt concentricity,and shear and compressive strengths of the anchoring solid are also enhanced in the reaming area.This ensures that the resin cartridge in the reaming area is completely stirred,which greatly improves the shear resistance of the reamingeanchoring solid.Meanwhile,the drilling performance,torsional force,and stirring efficiency of bolts are maximized and prevail over those of conventional bolts.
基金supported by the National Natural Science Foundation of China(No.61505013)the Postdoctoral Science Foundation of China(No.2016M591466)the Science and Technology Department Project of Jilin Province(Nos.20170204046GX and 20190101004JH)
文摘We examined a 1514 nm eye-safe passively Q-switched self-optical parametric oscillator. The nonlinear crystal is an a-cut Nd:MgO:PPLN crystal, and the size of the crystal was 6 mm × 2 mm × 30 mm with 0.4 at.%Nd^3+ doped and a grating period of 29.8 μm. When the crystal absorbed 12.8 W, the output maximum singlepulse energy reached 39 μJ, and a pulse width of 6.1 ns at a repetition rate of 5.4 kHz was obtained.The peak power was 6 kW, giving a slope efficiency of 42%.