Selective electrocatalytic semi-hydrogenation(ECSH)of alkynes in water using Cu catalysts is highly relevant for the production of value-added chemicals.However,achieving high olefin selectivity still poses extreme ch...Selective electrocatalytic semi-hydrogenation(ECSH)of alkynes in water using Cu catalysts is highly relevant for the production of value-added chemicals.However,achieving high olefin selectivity still poses extreme challenges due to the susceptibility of the copper cathode in a reduction environment.Herein,a small molecule modulation electrodeposition strategy is introduced that regulates the structure of Cubased materials through modification with citric acid(CA)ligands,aiming for highly active and selective ECSH.The as-prepared EDCu-CA electrode achieves more than 97%alkyne conversion and 99%olefin selectivity.In-situ Raman and Auger electron spectroscopy(AES)data provide evidence that active Cu^(+)sites can stably exist in the EDCu-CA during the catalytic process.Density functional theory(DFT)calculations indicate that the modulation by CA contributes to maintaining Cu in a positive valence state,and Cu^(+)can inhibit the over-hydrogenation of olefins.Moreover,by utilizing a large-area electrode for longterm electrolysis,g-level conversion and a 92%separation yield of olefin can be achieved,demonstrating a viable application prospect.This study offers a promising route for designing Cu-based catalysts for the highly selective electrocata lytic conversion of organic substrates to value-added chemicals in water.展开更多
Understanding the factors triggering slope failure is essential to ensure the safety of buildings and transportation infrastructure on slopes. Specifically,the failure of stabilizing piles due to groundwater migration...Understanding the factors triggering slope failure is essential to ensure the safety of buildings and transportation infrastructure on slopes. Specifically,the failure of stabilizing piles due to groundwater migration and freeze–thaw(FT) cycles is a significant factor causing slope failure. This study aims to investigate the transmedia seepage characteristics at slope–concrete stabilizing pile interface systems by using silty clay and concrete with varying microstructure characteristics under FT cycles. To this end, a self-developed indoor test device for transmedia water migration, combined with a macro-meso-micro multiscale testing approach, was used to analyze the laws and mechanisms of transmedia seepage at the interface systems. The effect of the medium's microstructure characteristics on the transmedia seepage behavior at the interface systems under FT cycles was also assessed. Results indicated that the transmedia water migration exhibited particularity due to the migration of soil particles and the low permeability characteristics of concrete. The water content in the media increased significantly within the range of 1/3–2/3 of the height from the interface for soil and within 5 mm from the interface for concrete.FT cycles promoted the increase and penetration of cracks within the medium, enhancing the permeability of the slope-concrete stabilizing pile interface systems.With the increase in FT cycles, the porosity inside the medium first decreased and then increased, and the porosity reached the minimum after 25 FT cycles and the maximum after 75 FT cycles, and the water content of the medium after water migration was positively correlated with the porosity. FT cycles also significantly influenced the temporal variation characteristics of soil moisture and the migration path of water in concrete. The study results could serve as a reference for related research on slope stability assessment.展开更多
ln order to improve the level of investment promotion and redouble effortsto enhance services,on February l9th,the 2025 Action Plan for StabilizingForeign lnvestment was released,proposing 20 measures in four aspects....ln order to improve the level of investment promotion and redouble effortsto enhance services,on February l9th,the 2025 Action Plan for StabilizingForeign lnvestment was released,proposing 20 measures in four aspects.Cur-rently,with increasing uncertainties in the external environment,China facesmultple difficulties and challenges in attracting foreign investment.展开更多
Augmenting the working voltage is an effective way to maximize the energy density of Ni-rich layered Li[Ni_(0.8)Co_(0.1)Mn_(0.1)]O_(2)(NCM)to approach its theoretical capacity.However,NCM suffers from structural degra...Augmenting the working voltage is an effective way to maximize the energy density of Ni-rich layered Li[Ni_(0.8)Co_(0.1)Mn_(0.1)]O_(2)(NCM)to approach its theoretical capacity.However,NCM suffers from structural degradation in deep delithiation state,which is often accompanied by severe surface lattice oxygen loss and transition metal dissolution,leading to restricted cycle life.Herein,a facile and effective surfacestrengthening strategy is proposed,in which Mn(OH)_(2)nanoshells are uniformly grown on the NCM surface as a Li~+capturer and then converted to thin spinel Li_(4)Mn_(5)O_(12)layers during subsequent hightemperature sintering.The resultant Li_(4)Mn_(5)O_(12)layers can enhance cathode-electrolyte interface electrochemical stability with inhibited electrolyte corrosion and accelerated Li~+kinetics.The theoretical calculations confirms that the Mn-O bonds formed at the interfaces can effectively decrease the oxygen activity,thereby further inhibiting the lattice oxygen release and structural degradation caused by the irreversible phase transition.Consequently,the Li_(4)Mn_(5)O_(12)-coated NCM displays high capacity retention of 80.3%and 94.9%at 1 C and 5 C compared to the pristine NCM(52.5%and 10.1%)after 200 cycles and can operate stably at 2.7-4.6 V and 60℃.The spinel Li_(4)Mn_(5)O_(12)-coating demonstrates an effective route to enhance the structural/electrochemical stability of NCM for next-generation advanced lithium-ion batteries.展开更多
Neutral oxygen evolution reaction(OER)is a crucial half-reaction for electrocatalytic chemical production under mild condition,but with limited development due to low activity and poor stability.Herein,a tungsten-dope...Neutral oxygen evolution reaction(OER)is a crucial half-reaction for electrocatalytic chemical production under mild condition,but with limited development due to low activity and poor stability.Herein,a tungsten-doped cobalt molybdate(WDCMO)catalyst was synthesized for efficient and durable OER under neutral electrolyte.It is demonstrated that catalyst reconstruction is suppressed by W doping,which stabilizes the Co-O-Mo point-to-point connection in CoMoO_(4) architecture and stimulates to a lower valence state of active sites over the surface phase.Thereby,the surface structure maintains to avoid compound dissolution caused by over-oxidation during OER.Meanwhile,the WDCMO catalyst promotes charge transfer and optimizes*OH intermediate adsorption,which improves reaction kinetics and intrinsic activity.Consequently,the WDCMO electrode exhibits an overpotential of 302 mV at 10 mA cm^(-2) in neutral electrolyte with an improvement of 182 mV compared with CoMoO4 electrode.Furthermore,W doping significantly improves the electrode stability from 50 h to more than 320 h,with a suppressive potential attenuation from 2.82 to 0.29 mV h^(-1).This work will shed new light on designing rational electrocatalysts for neutral OER.展开更多
Vitamin C,a potent antioxidant with broad therapeutic applications,is limited by rapid degradation under environmental stressors,which compromises its stability and bioactivity.This study addresses these limitations b...Vitamin C,a potent antioxidant with broad therapeutic applications,is limited by rapid degradation under environmental stressors,which compromises its stability and bioactivity.This study addresses these limitations by formulating a double nano-emulsion(W/O/W)system incorporating macadamia oil and tea tree oil,using homogenization and phase inversion temperature(PIT)techniques.Comprehensive physicochemical charac-terization,including droplet size,polydispersity index(PDI),zeta potential,turbidity,Fourier transform infrared spectroscopy(FTIR),and SEM,was conducted alongside stability assessments under varying pH,temperature,and storage conditions.The optimized nano-emulsions exhibited nanoscale droplet sizes(10-40 nm),low PDI values(indicating high uniformity),and robust stability.Interestingly,the formulation with 2%W/O loading,with a particle size of 11.57 nm and a PDI of 0.04,demonstrated an antioxidant capacity of 4622.62μg ascorbic acid equivalents(AA)/g,which was significantly higher(p<0.05)compared to both natural oils(macadamia oil:20.91μg AA/g,tea tree oil:16.86μg AA/g)and a 10%Vitamin C aqueous solution(592.94μg AA/g).FTIR analysis confirmed the molecular integrity of Vitamin C and its successful encapsulation with macadamia and tea tree oils,while SEM images revealed uniformly spherical and well-dispersed droplets.Moreover,the formulation retained its structural integrity and antioxidant functionality under diverse pH and thermal conditions.These findings underscore the potential of double nano-emulsion systems to overcome the stability challenges of Vitamin C,offering a promising approach to enhance its bioavailability and therapeutic performance in phar-maceutical and cosmetic applications.展开更多
Aqueous sodium-ion batteries(ASIBs) offer significant advantages for energy storage on a large scale,attributed to their economical cost,secure operatio n,and eco-friend ly natu re.Among the leading cathode materials ...Aqueous sodium-ion batteries(ASIBs) offer significant advantages for energy storage on a large scale,attributed to their economical cost,secure operatio n,and eco-friend ly natu re.Among the leading cathode materials for ASIBs,Na_(3)V_(2)(PO_(4))_(3)(NVP) exhibits excellent structural stability and a high Na+diffusion coefficient,making it a promising option.However,the high solubility of vanadium-based materials in aqueous electrolytes engenders suboptimal cycling stability for Na_(3)V_(2)(PO_(4))_(3),constraining its application in ASIBs.Herein,the Cr-substituted Na_(3)V_(1.3)Cr_(0.7)(PO_(4))3@C(NV_(1.3)Cr_(0.7)P) cathode material was synthesized via a simple sol-gel method.It is found that Cr substitution reduces the cell parameters of NV_(1.3)Cr_(0.7)P,effectively reinforcing the crystal structure.Furthermore,NV_(1.3)Cr_(0.7)P alters the Na^(+)insertion/extraction mechanism,transforming the typical two-phase reaction between Na_(1)V_(2)(PO_(4))_(3)and Na_(3)V_(2)(PO_(4))3into continuous solid-solution reactions with stable intermediates.The Cr substitution diminishes the sodium-ion diffusion energy barrier in NV_(1.3)Cr_(0.7)P,leading to smoother Na+insertion and extraction processes.Consequently,NV_(1.3)Cr_(0.7)P exhibits impressive cycling stability,retaining 74.8% of its capacity after 5,000 cycles at a current density of 5 A g^(-1),along with an outstanding rate performance of 79,2% at 10 A g^(-1).This work elucidates the stable Na^(+)insertion/extraction processes in Cr-substituted NV_(1.3)Cr_(0.7)P,offering insights into the application of vanadium-based materials in aqueous sodium-ion batteries.展开更多
With the construction of the Three Gorges Reservoir dam,frequent reservoir landslide events have been recorded.In recent years,multi-row stabilizing piles(MRSPs)have been used to stabilize massive reservoir landslides...With the construction of the Three Gorges Reservoir dam,frequent reservoir landslide events have been recorded.In recent years,multi-row stabilizing piles(MRSPs)have been used to stabilize massive reservoir landslides in China.In this study,two centrifuge model tests were carried out to study the unreinforced and MRSP-reinforced slopes subjected to reservoir water level(RWL)operation,using the Taping landslide as a prototype.The results indicate that the RWL rising can provide lateral support within the submerged zone and then produce the inward seepage force,eventually strengthening the slope stability.However,a rapid RWL drawdown may induce outward seepage forces and a sudden debuttressing effect,consequently reducing the effective soil normal stress and triggering partial pre-failure within the RWL fluctuation zone.Furthermore,partial deformation and subsequent soil structure damage generate excess pore water pressures,ultimately leading to the overall failure of the reservoir landslide.This study also reveals that a rapid increase in the downslope driving force due to RWL drawdown significantly intensifies the lateral earth pressures exerted on the MRSPs.Conversely,the MRSPs possess a considerable reinforcement effect on the reservoir landslide,transforming the overall failure into a partial deformation and failure situated above and in front of the MRSPs.The mechanical transfer behavior observed in the MRSPs demonstrates a progressive alteration in relation to RWL fluctuations.As the RWL rises,the mechanical states among MRSPs exhibit a growing imbalance.The shear force transfer factor(i.e.the ratio of shear forces on pile of the n th row to that of the first row)increases significantly with the RWL drawdown.This indicates that the mechanical states among MRSPs tend toward an enhanced equilibrium.The insights gained from this study contribute to a more comprehensive understanding of the failure mechanisms of reservoir landslides and the mechanical behavior of MRSPs in reservoir banks.展开更多
The pressing environmental concerns and the depletion of fossil fuel reserves necessitate a transition toward sustainable energy sources.Ethanol,a renewable biomass-derived fuel,is a promising alternative due to its a...The pressing environmental concerns and the depletion of fossil fuel reserves necessitate a transition toward sustainable energy sources.Ethanol,a renewable biomass-derived fuel,is a promising alternative due to its availability and high energy density.This study investigates the synthesis of gold nanoparticles(Au NPs)via a square-wave pulse deposition technique,aiming to enhance catalytic activity for ethanol electrooxidation.By varying pulse durations,we were able to exert precise control over Au NP size and distribution without stabilizing agents.Characterization using field emission scanning electron microscopy and X-ray diffraction techniques confirmed the formation of clustered nanoparticles of metallic gold phase.Electrochemical characteristics analyses revealed that Au NPs synthesized with a 900 ms pulse duration exhibited the lowest charge transfer resistance and the highest electrochemically active surface area.The electrocatalytic performance test of these Au NPs demonstrated an anodic current density of 2.5 mA cm^-(2)and a Tafel slope of 78 mV dec^(-1),indicating superior catalytic performance and reaction kinetics.Additionally,the Au NPs showed high resistance to poisoning,as evidenced by a low j_(b)/j_(f)ratio of 0.28 and stable chronoamperometric response.These findings underscore the potential of this synthesis method for producing high-performance electrocatalysts utilized in exploiting ethanol's potential as an environmentally friendly energy carrier.展开更多
Thermo-responsive nanocomposites have recently emerged as potential nanoplugging agents for shale stabilization in high-temperature water-based drilling fluids(WBDFs). However, their inhibitory properties have not bee...Thermo-responsive nanocomposites have recently emerged as potential nanoplugging agents for shale stabilization in high-temperature water-based drilling fluids(WBDFs). However, their inhibitory properties have not been very effective in high-temperature drilling operations. Thermo-responsive Janus nanocomposites are expected to strongly interact with clay particles from the inward hemisphere of nanomaterials, which drive the establishment of a tighter hydrophobic membrane over the shale surface at the outward hemisphere under geothermal conditions for shale stabilization. This work combines the synergistic benefits of thermo-responsive and zwitterionic nanomaterials to synchronously enhance the chemical inhibitions and plugging performances in shale under harsh conditions. A novel thermoresponsive Janus nanosilica(TRJS) exhibiting zwitterionic character was synthesized, characterized,and assessed as shale stabilizer for WBDFs at high temperatures. Compared to pristine nanosilica(Si NP)and symmetrical thermo-responsive nanosilica(TRS), TRJS exhibited anti-polyelectrolyte behaviour, in which electrolyte ions screened the electrostatic attraction between the charged particles, potentially stabilizing nanomaterial in hostile shaly environments(i.e., up to saturated brine or API brine). Macroscopically, TRJS exhibited higher chemical inhibition than Si NP and TRS in brine, prompting a better capability to control pressure penetration. TRJS adsorbed onto the clay surface via chemisorption and hydrogen bonding, and the interactions became substantial in brine, according to the results of electrophoretic mobility, surface wettability, and X-ray diffraction. Thus, contributing to the firm trapping of TRJS into the nanopore structure of the shale, triggering the formation of a tight hydrophobic membrane over the shale surface from the outward hemisphere. The addition of TRJS into WBDF had no deleterious effect on fluid properties after hot-treatment at 190℃, implying that TRJS could find potential use as a shale stabilizer in WBDFs in hostile environments.展开更多
Niobium alloys have found extensive application in industries,such as aerospace,nuclear reactor,and emerging electronic technologies,owing to their high melting point,low density,and remarkable formability.Nevertheles...Niobium alloys have found extensive application in industries,such as aerospace,nuclear reactor,and emerging electronic technologies,owing to their high melting point,low density,and remarkable formability.Nevertheless,they still fall short in terms of comprehensive strength,toughness,and thermal stability when subjected to complex impacts and/or torsional forces during service.Here,a dual-phase(BCC/FCC)Nb alloy with attractive mechanical properties and thermal stability was designed by tuning stable element C in the Nb-BCC matrix assisted by hot deformation and aging processes.Our findings reveal that the formation of discontinuous carbides at the grain boundary promotes the phase transformation of the matrix from BCC to FCC(K-S orientation relationship),resulting in the formation of FCC thin layers and nano particles.This unique configuration hinders the slipping of dislocations during deformation and impedes the degeneration of microstructures during the thermal cycling process from 200°C to 900°C.Moreover,the discontinuous carbides at GBs provide channels to transfer dislocations between various phases and/or grains,which results in attractive mechanical properties and thermal stability.The ultimate tensile strength,yield strength,elongation,and elasticity modulus of the designed Nb alloy reach impressive values of 790.5 MPa,436.5 MPa,39.1%,and 63.5 MPa,respectively.These observations provide guidelines for designing dual-phase Nb alloys with remarkable strength,toughness,and thermal stability for aerospace applications by tuning the stabilizing element C in the Nb-BCC matrix.展开更多
Solution processability significantly advances the development of highly-efficient perovskite solar cells.However,the precursor solution tends to undergo irreversible degradation reactions,impairing the device perform...Solution processability significantly advances the development of highly-efficient perovskite solar cells.However,the precursor solution tends to undergo irreversible degradation reactions,impairing the device performance and reproducibility.Here,we utilize a reductive natural amino acid,Nacetylcysteine(NALC),to stabilize the precursor solution for printable carbon-based hole-conductorfree mesoscopic perovskite solar cells.We find that I_(2) can be generated in the aged solution containing methylammonium iodide(MI) in an inert atmosphere and speed up the MA-FA^(+)(formamidinium) reaction which produces large-size cations and hinders the formation of perovskite phase.NALC effectively stabilizes the precursor via its sulfhydryl group which reduces I_(2) back to I^(-)and provides H^(+).The NALC-stabilized precursor which is aged for 1440 h leads to devices with a power conversion efficiency equivalent to 98% of that for devices prepared with the fresh precursor.Furthermore,NALC improves the device power conversion efficiency from 16.16% to 18.41% along with enhanced stability under atmospheric conditions by modifying grain boundaries in perovskite films and reducing associated defects.展开更多
High-density coherent nanoprecipitates have been widely introduced into the design of new structural materials to achieve a superior strength-ductility balance.However,the thermal instability of nanostructures limits ...High-density coherent nanoprecipitates have been widely introduced into the design of new structural materials to achieve a superior strength-ductility balance.However,the thermal instability of nanostructures limits their fabrication and application.In this study,we investigated the temporal evolution of nanoprecipitates in coherent nanoprecipitation-strengthened Al_(0.5)Cr_(0.9)FeNi_(2.5)V_(0.2)high-entropy alloy during isothermal aging.When annealed at 600℃for more than 100 h,we found that its nanoprecipitates were invariably stable,with no obvious changes occurring in terms of morphology and distribution.The excellent stability was mainly attributed to the restricted state of interface migration and diffusion owing to the hierarchical nanostructure.The Cr-enriched nano-lamellar BCC phase divided the Cr-depleted FCC(L1_(2))matrix,forming barriers to long-range diffusion and resulting in a kinetically slow coarsening rate.As the nano-lamellar BCC phase spheroidized as the aging temperature increased to 700℃,the diffusion barriers were destroyed.Remarkable coarsening occurred after that,which further verified the significant effect of the nano-lamellar BCC phase on the microstructural stability.These results provide a paradigm for designing alloys stabilized via hierarchical nanostructure,achieving good strength-ductility synergy while excellent thermal stability.展开更多
The microstructures of as-extruded and stabilizing heat-treated Zn-10Al-2Cu-0.02Ti alloys were observed by scanning electron microscopy,transmission electron microscopy,electron probe microanalysis and X-ray diffracti...The microstructures of as-extruded and stabilizing heat-treated Zn-10Al-2Cu-0.02Ti alloys were observed by scanning electron microscopy,transmission electron microscopy,electron probe microanalysis and X-ray diffraction analysis techniques.The change in structure after heat treatment and its effects on room temperature creep behavior were investigated by creep experiments at constant stress and slow strain rate tensile tests.The results show that after stabilizing heat treatment((350℃,30 min,water-cooling)+(100℃,12 h,air-cooling)),the amount of α+η lamellar structure decreases,while the amount of cellular and granular structure increases.The heat-treated Zn-10Al-2Cu-0.02Ti alloy exhibits better creep resistance than the as-extruded alloy,and the rate of steady state creep decreases by 96.9% after stabilizing heat treatment.展开更多
A brand new method of automatic north seeking/sight stabilizing is introduced for usage in land fighting vehicles such as tank, etc. Some inertial devices are installed additionally on the platform along with relat...A brand new method of automatic north seeking/sight stabilizing is introduced for usage in land fighting vehicles such as tank, etc. Some inertial devices are installed additionally on the platform along with relative control circuits to make its function of North seeking possible. Double position calculation is adopted in this method, and by alignment at two sites the azimuth angle can be figured out. Also the orientation and the horizontal shifts of the gyro are simultaneously measured and compensated so as to improve the accuracy of north seeking. The system can automatically seek north when the vehicle is immobile. And the time consumption is no more than 5.5 min. Besides, the system can keep azimuth angle and provide tilt angle and pitch angle of the vehicle.展开更多
The bending behavior of double-row stabilizing plies is associated with the constructional time delay(CTD),which can be defined as the time interval between the installations of the front stabilizing pile and the rear...The bending behavior of double-row stabilizing plies is associated with the constructional time delay(CTD),which can be defined as the time interval between the installations of the front stabilizing pile and the rear stabilizing pile.This paper investigates the effect of CTD on the bending moments of double-row stabilizing piles and a method for determining the optimal CTD is proposed.The stabilizing pile is modeled as a cantilever pile embedded in the Winkler elastic foundation.A triangular distributed earth pressure is assumed on the pile segment in the sliding layer.The front stabilizing pile and the rear stabilizing pile are connected by a beam with pinned joints.The analytical solutions of bending moments on the front and the rear stabilizing piles are derived and the accuracy of bending moment solutions is validated by comparing the tensile strain measured from the Hongyan landslide project,Taizhou,Zhejiang,China.It is concluded that CTD has a significant influence on the bending moments of double-row stabilizing piles.An optimal CTD can be obtained when the maximum tensile stress in the front stabilizing pile is equal to that in the rear stabilizing pile,which is 1.4 months for the Hongyan landslide project.展开更多
A new technique was introduced for sand stabilization and re-vegetation by use of lignin sand stabilizing material(LSSM). LSSM is a reconstructed organic compound with lignin as the most dominant component from the ex...A new technique was introduced for sand stabilization and re-vegetation by use of lignin sand stabilizing material(LSSM). LSSM is a reconstructed organic compound with lignin as the most dominant component from the extracts of black-liquor issued by straw pulp paper mills. Unlike the polyvinyl acetate or foamed asphalt commonly used for dune stabilization, the new material is plant-friendly and can be used with virescence actions simultaneously. The field experimental study was conducted since 2001 in China's Northwest Ningxia Hui Autonomous Region and has been proved that LSSM is effective in stabilizing the fugitive dunes, making the arenaceous plants survive and the bare dune vegetative. The advisable solution concentration is 2% and the optimal field spraying quantity is 2 5 L/m^2 The soil nutrients of the stabilized and greened dune, such as organic matter, available phosphorous and total nitrogen are all increased compared with the control treatment, which is certainly helpful to the growth of arenaceous plants. The technique is worthwhile to be popularized because it is provided not only a new method for desertification control but also an outlet for cleaning contaminants issued from the straw paper mills.展开更多
Plant regrowth capacity and soil protection were investigated using three flooding-tolerant Yangtze River riverside species (Arundinella anomala, Hemartria compressa and Cynodon dactylon). The root and leaf surface ...Plant regrowth capacity and soil protection were investigated using three flooding-tolerant Yangtze River riverside species (Arundinella anomala, Hemartria compressa and Cynodon dactylon). The root and leaf surface growth, the plant regrowth capacity and the mitigation of soil runoff were analyzed using potted plants that were covered with 5, 10 and 18 cm new sediments, respectively. A. anomala reacted most slowly to the recovery from new sediments, while H. compressa had the highest recovery rates. The latter could produce 24 times the initial root length and 41 times its original leaf surface during the growth period of 12 weeks. C. dactyion showed no significant change in growth in relation to the rising sediment thickness, which means that even 18 cm of new sediments were tolerated by C. dactylon. Erosion tests showed that all three plant species can reduce the soil runoff by more than 63%. Compared to other species, A. anomala was less capable of stabilizing new sediments. The soil protecting abilities of H. compressa decreased after more than 10 cm of new sediments. C. dactyion showed the best soil retention compared to the other species examined, since it could reduce the soil runoff up to 87%. Consequently, C. dactylon was found to be significantly better for soil-protection plant species than A. anomala and H. compressa given the conditions at the Three Gorges Reservoir.展开更多
The paper presents an improved plane layout for stabilizing piles based on a proposed piecewise function expression for the irregular driving force. Based on the specific morphological characteristics of a highway lan...The paper presents an improved plane layout for stabilizing piles based on a proposed piecewise function expression for the irregular driving force. Based on the specific morphological characteristics of a highway landslide, the piecewise function is used to calculate the irregular driving force by dividing the landslide into several sub-areas.Furthermore, the reasonable layout range and pile spacing can be obtained based on the piecewise function expression of the irregular driving force and on relevant research results of the plane layout for stabilizing piles. Therefore, an improved plane layout of stabilizing piles is presented in consideration of a piecewise function expression of the irregular driving force. A highway landslide located in eastern Guizhou Province, China, is analyzed as a case study using the proposed method. The results demonstrate that the theory presented in this paper provides improved economic benefits and can reduce the requirednumber of stabilizing piles by 28.6% compared with the conventional plane layout scheme.展开更多
Objective To investigate whether α-hemoglobin stabilizing protein (AHSP), the α-globin-specific molecular chaperone, is regulated by erythroid transcription factor NF-E2. Methods We established the stable cell line ...Objective To investigate whether α-hemoglobin stabilizing protein (AHSP), the α-globin-specific molecular chaperone, is regulated by erythroid transcription factor NF-E2. Methods We established the stable cell line with NF-E2p45 (the larger subunit of NF-E2) short hairpin RNA to silence its expression. Western blot, real-time polymerase chain reaction, and chromatin immunoprecipitation (ChIP) analysis were performed to detect the expression of AHSP, the histone modifications at AHSP gene locus, and the binding of GATA-1 at the AHSP promoter with NF-E2p45 deficiency. ChIP was also carried out in dimethyl sulfoxide (DMSO)-induced DS19 cells and estrogen-induced G1E-ER4 cells to examine NF-E2 binding to the AHSP gene locus and its changes during cell erythroid differentiation. Finally, luciferase assay was applied in HeLa cells transfected with AHSP promoter fragments to examine AHSP promoter activity in the presence of exogenous NF-E2p45. Results We found that AHSP expression was highly dependent on NF-E2p45. NF-E2 bound to the regions across AHSP gene locus in vivo, and the transcription of AHSP was transactivated by exogenous NF-E2p45. In addition, we observed the decrease of H3K4 trimethylation and GATA-1 occupancy at the AHSP gene locus in NF-E2p45-deficient cells. Restoration of GATA-1 in G1E-ER4 cells in turn led to increased DNA binding of NF-E2p45. Conclusion NF-E2 may play an important role in AHSP gene regulation, providing new insights into the molecular mechanisms underlying the erythroid-specific expression of AHSP as well as new possibilities for β-thalassemia treatment.展开更多
基金financially supported by the National Natural Science Foundation of China(NSFC)(22179056,22172018)the Liaoning Revitalization Talents Program(XLYC2002097,1807210)+2 种基金the Key Projects of Liaoning Provincial Education Department(JYTZD2023001)the Fundamental Research Funds for the Central Universities(DUT23LAB611)Yingkou Talents Program。
文摘Selective electrocatalytic semi-hydrogenation(ECSH)of alkynes in water using Cu catalysts is highly relevant for the production of value-added chemicals.However,achieving high olefin selectivity still poses extreme challenges due to the susceptibility of the copper cathode in a reduction environment.Herein,a small molecule modulation electrodeposition strategy is introduced that regulates the structure of Cubased materials through modification with citric acid(CA)ligands,aiming for highly active and selective ECSH.The as-prepared EDCu-CA electrode achieves more than 97%alkyne conversion and 99%olefin selectivity.In-situ Raman and Auger electron spectroscopy(AES)data provide evidence that active Cu^(+)sites can stably exist in the EDCu-CA during the catalytic process.Density functional theory(DFT)calculations indicate that the modulation by CA contributes to maintaining Cu in a positive valence state,and Cu^(+)can inhibit the over-hydrogenation of olefins.Moreover,by utilizing a large-area electrode for longterm electrolysis,g-level conversion and a 92%separation yield of olefin can be achieved,demonstrating a viable application prospect.This study offers a promising route for designing Cu-based catalysts for the highly selective electrocata lytic conversion of organic substrates to value-added chemicals in water.
基金financially supported by Jilin Provincial Natural Science Foundation (No.20220101164JC)。
文摘Understanding the factors triggering slope failure is essential to ensure the safety of buildings and transportation infrastructure on slopes. Specifically,the failure of stabilizing piles due to groundwater migration and freeze–thaw(FT) cycles is a significant factor causing slope failure. This study aims to investigate the transmedia seepage characteristics at slope–concrete stabilizing pile interface systems by using silty clay and concrete with varying microstructure characteristics under FT cycles. To this end, a self-developed indoor test device for transmedia water migration, combined with a macro-meso-micro multiscale testing approach, was used to analyze the laws and mechanisms of transmedia seepage at the interface systems. The effect of the medium's microstructure characteristics on the transmedia seepage behavior at the interface systems under FT cycles was also assessed. Results indicated that the transmedia water migration exhibited particularity due to the migration of soil particles and the low permeability characteristics of concrete. The water content in the media increased significantly within the range of 1/3–2/3 of the height from the interface for soil and within 5 mm from the interface for concrete.FT cycles promoted the increase and penetration of cracks within the medium, enhancing the permeability of the slope-concrete stabilizing pile interface systems.With the increase in FT cycles, the porosity inside the medium first decreased and then increased, and the porosity reached the minimum after 25 FT cycles and the maximum after 75 FT cycles, and the water content of the medium after water migration was positively correlated with the porosity. FT cycles also significantly influenced the temporal variation characteristics of soil moisture and the migration path of water in concrete. The study results could serve as a reference for related research on slope stability assessment.
文摘ln order to improve the level of investment promotion and redouble effortsto enhance services,on February l9th,the 2025 Action Plan for StabilizingForeign lnvestment was released,proposing 20 measures in four aspects.Cur-rently,with increasing uncertainties in the external environment,China facesmultple difficulties and challenges in attracting foreign investment.
基金financial support from the Key Research and Development Project in Shaanxi Province(2023-YBGY-446)the Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering(No.2022SX-TD003)+1 种基金the Natural Science Basic Research Program of Shaanxi(No.2024JC-YBQN-0108)the Key Laboratory of Interface Science and Engineering in Advanced Materials,Ministry of Education(KLISEAM202202)。
文摘Augmenting the working voltage is an effective way to maximize the energy density of Ni-rich layered Li[Ni_(0.8)Co_(0.1)Mn_(0.1)]O_(2)(NCM)to approach its theoretical capacity.However,NCM suffers from structural degradation in deep delithiation state,which is often accompanied by severe surface lattice oxygen loss and transition metal dissolution,leading to restricted cycle life.Herein,a facile and effective surfacestrengthening strategy is proposed,in which Mn(OH)_(2)nanoshells are uniformly grown on the NCM surface as a Li~+capturer and then converted to thin spinel Li_(4)Mn_(5)O_(12)layers during subsequent hightemperature sintering.The resultant Li_(4)Mn_(5)O_(12)layers can enhance cathode-electrolyte interface electrochemical stability with inhibited electrolyte corrosion and accelerated Li~+kinetics.The theoretical calculations confirms that the Mn-O bonds formed at the interfaces can effectively decrease the oxygen activity,thereby further inhibiting the lattice oxygen release and structural degradation caused by the irreversible phase transition.Consequently,the Li_(4)Mn_(5)O_(12)-coated NCM displays high capacity retention of 80.3%and 94.9%at 1 C and 5 C compared to the pristine NCM(52.5%and 10.1%)after 200 cycles and can operate stably at 2.7-4.6 V and 60℃.The spinel Li_(4)Mn_(5)O_(12)-coating demonstrates an effective route to enhance the structural/electrochemical stability of NCM for next-generation advanced lithium-ion batteries.
文摘Neutral oxygen evolution reaction(OER)is a crucial half-reaction for electrocatalytic chemical production under mild condition,but with limited development due to low activity and poor stability.Herein,a tungsten-doped cobalt molybdate(WDCMO)catalyst was synthesized for efficient and durable OER under neutral electrolyte.It is demonstrated that catalyst reconstruction is suppressed by W doping,which stabilizes the Co-O-Mo point-to-point connection in CoMoO_(4) architecture and stimulates to a lower valence state of active sites over the surface phase.Thereby,the surface structure maintains to avoid compound dissolution caused by over-oxidation during OER.Meanwhile,the WDCMO catalyst promotes charge transfer and optimizes*OH intermediate adsorption,which improves reaction kinetics and intrinsic activity.Consequently,the WDCMO electrode exhibits an overpotential of 302 mV at 10 mA cm^(-2) in neutral electrolyte with an improvement of 182 mV compared with CoMoO4 electrode.Furthermore,W doping significantly improves the electrode stability from 50 h to more than 320 h,with a suppressive potential attenuation from 2.82 to 0.29 mV h^(-1).This work will shed new light on designing rational electrocatalysts for neutral OER.
基金Ho Chi Minh City University of Technology(HCMUT),VNU-HCM for supporting this study.
文摘Vitamin C,a potent antioxidant with broad therapeutic applications,is limited by rapid degradation under environmental stressors,which compromises its stability and bioactivity.This study addresses these limitations by formulating a double nano-emulsion(W/O/W)system incorporating macadamia oil and tea tree oil,using homogenization and phase inversion temperature(PIT)techniques.Comprehensive physicochemical charac-terization,including droplet size,polydispersity index(PDI),zeta potential,turbidity,Fourier transform infrared spectroscopy(FTIR),and SEM,was conducted alongside stability assessments under varying pH,temperature,and storage conditions.The optimized nano-emulsions exhibited nanoscale droplet sizes(10-40 nm),low PDI values(indicating high uniformity),and robust stability.Interestingly,the formulation with 2%W/O loading,with a particle size of 11.57 nm and a PDI of 0.04,demonstrated an antioxidant capacity of 4622.62μg ascorbic acid equivalents(AA)/g,which was significantly higher(p<0.05)compared to both natural oils(macadamia oil:20.91μg AA/g,tea tree oil:16.86μg AA/g)and a 10%Vitamin C aqueous solution(592.94μg AA/g).FTIR analysis confirmed the molecular integrity of Vitamin C and its successful encapsulation with macadamia and tea tree oils,while SEM images revealed uniformly spherical and well-dispersed droplets.Moreover,the formulation retained its structural integrity and antioxidant functionality under diverse pH and thermal conditions.These findings underscore the potential of double nano-emulsion systems to overcome the stability challenges of Vitamin C,offering a promising approach to enhance its bioavailability and therapeutic performance in phar-maceutical and cosmetic applications.
基金financially supported by the Scientific and Technological Plan Project of Guizhou Province ([2024]054)Additional support came from the Industry and Education Combination Innovation Platform of Intelligent Manufacturing and Graduate Joint Training Base at Guizhou University (2020-520000-83-01324061)the Guizhou Engineering Research Center for Smart Services (2203-520102-04-04-298868)。
文摘Aqueous sodium-ion batteries(ASIBs) offer significant advantages for energy storage on a large scale,attributed to their economical cost,secure operatio n,and eco-friend ly natu re.Among the leading cathode materials for ASIBs,Na_(3)V_(2)(PO_(4))_(3)(NVP) exhibits excellent structural stability and a high Na+diffusion coefficient,making it a promising option.However,the high solubility of vanadium-based materials in aqueous electrolytes engenders suboptimal cycling stability for Na_(3)V_(2)(PO_(4))_(3),constraining its application in ASIBs.Herein,the Cr-substituted Na_(3)V_(1.3)Cr_(0.7)(PO_(4))3@C(NV_(1.3)Cr_(0.7)P) cathode material was synthesized via a simple sol-gel method.It is found that Cr substitution reduces the cell parameters of NV_(1.3)Cr_(0.7)P,effectively reinforcing the crystal structure.Furthermore,NV_(1.3)Cr_(0.7)P alters the Na^(+)insertion/extraction mechanism,transforming the typical two-phase reaction between Na_(1)V_(2)(PO_(4))_(3)and Na_(3)V_(2)(PO_(4))3into continuous solid-solution reactions with stable intermediates.The Cr substitution diminishes the sodium-ion diffusion energy barrier in NV_(1.3)Cr_(0.7)P,leading to smoother Na+insertion and extraction processes.Consequently,NV_(1.3)Cr_(0.7)P exhibits impressive cycling stability,retaining 74.8% of its capacity after 5,000 cycles at a current density of 5 A g^(-1),along with an outstanding rate performance of 79,2% at 10 A g^(-1).This work elucidates the stable Na^(+)insertion/extraction processes in Cr-substituted NV_(1.3)Cr_(0.7)P,offering insights into the application of vanadium-based materials in aqueous sodium-ion batteries.
基金funded by Chongqing Natural Science Key Program of China(Grant No.cstc2020jcyj-zdxmX0019)China Geological Survey Program(Grant No.DD20190637/DD20221748).
文摘With the construction of the Three Gorges Reservoir dam,frequent reservoir landslide events have been recorded.In recent years,multi-row stabilizing piles(MRSPs)have been used to stabilize massive reservoir landslides in China.In this study,two centrifuge model tests were carried out to study the unreinforced and MRSP-reinforced slopes subjected to reservoir water level(RWL)operation,using the Taping landslide as a prototype.The results indicate that the RWL rising can provide lateral support within the submerged zone and then produce the inward seepage force,eventually strengthening the slope stability.However,a rapid RWL drawdown may induce outward seepage forces and a sudden debuttressing effect,consequently reducing the effective soil normal stress and triggering partial pre-failure within the RWL fluctuation zone.Furthermore,partial deformation and subsequent soil structure damage generate excess pore water pressures,ultimately leading to the overall failure of the reservoir landslide.This study also reveals that a rapid increase in the downslope driving force due to RWL drawdown significantly intensifies the lateral earth pressures exerted on the MRSPs.Conversely,the MRSPs possess a considerable reinforcement effect on the reservoir landslide,transforming the overall failure into a partial deformation and failure situated above and in front of the MRSPs.The mechanical transfer behavior observed in the MRSPs demonstrates a progressive alteration in relation to RWL fluctuations.As the RWL rises,the mechanical states among MRSPs exhibit a growing imbalance.The shear force transfer factor(i.e.the ratio of shear forces on pile of the n th row to that of the first row)increases significantly with the RWL drawdown.This indicates that the mechanical states among MRSPs tend toward an enhanced equilibrium.The insights gained from this study contribute to a more comprehensive understanding of the failure mechanisms of reservoir landslides and the mechanical behavior of MRSPs in reservoir banks.
基金supported by the National Research and Innovation Agency(BRIN)and Lembaga Pengelola Dana Pendidikan(LPDP)Ministry of Finance,Republic of Indonesia through Riset dan Inovasi Untuk Indonesia Maju(RIIM)scheme batch 2 with contract number 1/PG.02.00.PT/LPPM/IV/2024(110/IV/KS/11/2022).
文摘The pressing environmental concerns and the depletion of fossil fuel reserves necessitate a transition toward sustainable energy sources.Ethanol,a renewable biomass-derived fuel,is a promising alternative due to its availability and high energy density.This study investigates the synthesis of gold nanoparticles(Au NPs)via a square-wave pulse deposition technique,aiming to enhance catalytic activity for ethanol electrooxidation.By varying pulse durations,we were able to exert precise control over Au NP size and distribution without stabilizing agents.Characterization using field emission scanning electron microscopy and X-ray diffraction techniques confirmed the formation of clustered nanoparticles of metallic gold phase.Electrochemical characteristics analyses revealed that Au NPs synthesized with a 900 ms pulse duration exhibited the lowest charge transfer resistance and the highest electrochemically active surface area.The electrocatalytic performance test of these Au NPs demonstrated an anodic current density of 2.5 mA cm^-(2)and a Tafel slope of 78 mV dec^(-1),indicating superior catalytic performance and reaction kinetics.Additionally,the Au NPs showed high resistance to poisoning,as evidenced by a low j_(b)/j_(f)ratio of 0.28 and stable chronoamperometric response.These findings underscore the potential of this synthesis method for producing high-performance electrocatalysts utilized in exploiting ethanol's potential as an environmentally friendly energy carrier.
基金financially supported by the National Natural Science Foundation of China(Grant No.52150410427)the Key Support Program for Foreign Experts of the Ministry of Science and Technology of the People's Republic of China(No.wgxz2022057)funding for post-doctoral work by the Department of Human Resources and Social Security of Hubei Province。
文摘Thermo-responsive nanocomposites have recently emerged as potential nanoplugging agents for shale stabilization in high-temperature water-based drilling fluids(WBDFs). However, their inhibitory properties have not been very effective in high-temperature drilling operations. Thermo-responsive Janus nanocomposites are expected to strongly interact with clay particles from the inward hemisphere of nanomaterials, which drive the establishment of a tighter hydrophobic membrane over the shale surface at the outward hemisphere under geothermal conditions for shale stabilization. This work combines the synergistic benefits of thermo-responsive and zwitterionic nanomaterials to synchronously enhance the chemical inhibitions and plugging performances in shale under harsh conditions. A novel thermoresponsive Janus nanosilica(TRJS) exhibiting zwitterionic character was synthesized, characterized,and assessed as shale stabilizer for WBDFs at high temperatures. Compared to pristine nanosilica(Si NP)and symmetrical thermo-responsive nanosilica(TRS), TRJS exhibited anti-polyelectrolyte behaviour, in which electrolyte ions screened the electrostatic attraction between the charged particles, potentially stabilizing nanomaterial in hostile shaly environments(i.e., up to saturated brine or API brine). Macroscopically, TRJS exhibited higher chemical inhibition than Si NP and TRS in brine, prompting a better capability to control pressure penetration. TRJS adsorbed onto the clay surface via chemisorption and hydrogen bonding, and the interactions became substantial in brine, according to the results of electrophoretic mobility, surface wettability, and X-ray diffraction. Thus, contributing to the firm trapping of TRJS into the nanopore structure of the shale, triggering the formation of a tight hydrophobic membrane over the shale surface from the outward hemisphere. The addition of TRJS into WBDF had no deleterious effect on fluid properties after hot-treatment at 190℃, implying that TRJS could find potential use as a shale stabilizer in WBDFs in hostile environments.
基金supported financially by the National Natural Science Foundation of China(No.51901252)the Hunan Province Natural Science Foundation(No.2023JJ30684)the support from the State Key Laboratory of Powder Metallurgy,Central South University,Changsha,China.
文摘Niobium alloys have found extensive application in industries,such as aerospace,nuclear reactor,and emerging electronic technologies,owing to their high melting point,low density,and remarkable formability.Nevertheless,they still fall short in terms of comprehensive strength,toughness,and thermal stability when subjected to complex impacts and/or torsional forces during service.Here,a dual-phase(BCC/FCC)Nb alloy with attractive mechanical properties and thermal stability was designed by tuning stable element C in the Nb-BCC matrix assisted by hot deformation and aging processes.Our findings reveal that the formation of discontinuous carbides at the grain boundary promotes the phase transformation of the matrix from BCC to FCC(K-S orientation relationship),resulting in the formation of FCC thin layers and nano particles.This unique configuration hinders the slipping of dislocations during deformation and impedes the degeneration of microstructures during the thermal cycling process from 200°C to 900°C.Moreover,the discontinuous carbides at GBs provide channels to transfer dislocations between various phases and/or grains,which results in attractive mechanical properties and thermal stability.The ultimate tensile strength,yield strength,elongation,and elasticity modulus of the designed Nb alloy reach impressive values of 790.5 MPa,436.5 MPa,39.1%,and 63.5 MPa,respectively.These observations provide guidelines for designing dual-phase Nb alloys with remarkable strength,toughness,and thermal stability for aerospace applications by tuning the stabilizing element C in the Nb-BCC matrix.
基金financial support from the National Natural Science Foundation of China(grant nos.52172198,51902117,and 91733301)。
文摘Solution processability significantly advances the development of highly-efficient perovskite solar cells.However,the precursor solution tends to undergo irreversible degradation reactions,impairing the device performance and reproducibility.Here,we utilize a reductive natural amino acid,Nacetylcysteine(NALC),to stabilize the precursor solution for printable carbon-based hole-conductorfree mesoscopic perovskite solar cells.We find that I_(2) can be generated in the aged solution containing methylammonium iodide(MI) in an inert atmosphere and speed up the MA-FA^(+)(formamidinium) reaction which produces large-size cations and hinders the formation of perovskite phase.NALC effectively stabilizes the precursor via its sulfhydryl group which reduces I_(2) back to I^(-)and provides H^(+).The NALC-stabilized precursor which is aged for 1440 h leads to devices with a power conversion efficiency equivalent to 98% of that for devices prepared with the fresh precursor.Furthermore,NALC improves the device power conversion efficiency from 16.16% to 18.41% along with enhanced stability under atmospheric conditions by modifying grain boundaries in perovskite films and reducing associated defects.
基金supported by the National Na-ture Science Foundation of China(Nos.U2241234,52201152,and 52301127)the China Postdoctoral Science Foundation(No.2022M720150)the Advanced Photon Source at Argonne National Laboratory was supported by the US Department of En-ergy(No.DE-AC02-06CH11357).
文摘High-density coherent nanoprecipitates have been widely introduced into the design of new structural materials to achieve a superior strength-ductility balance.However,the thermal instability of nanostructures limits their fabrication and application.In this study,we investigated the temporal evolution of nanoprecipitates in coherent nanoprecipitation-strengthened Al_(0.5)Cr_(0.9)FeNi_(2.5)V_(0.2)high-entropy alloy during isothermal aging.When annealed at 600℃for more than 100 h,we found that its nanoprecipitates were invariably stable,with no obvious changes occurring in terms of morphology and distribution.The excellent stability was mainly attributed to the restricted state of interface migration and diffusion owing to the hierarchical nanostructure.The Cr-enriched nano-lamellar BCC phase divided the Cr-depleted FCC(L1_(2))matrix,forming barriers to long-range diffusion and resulting in a kinetically slow coarsening rate.As the nano-lamellar BCC phase spheroidized as the aging temperature increased to 700℃,the diffusion barriers were destroyed.Remarkable coarsening occurred after that,which further verified the significant effect of the nano-lamellar BCC phase on the microstructural stability.These results provide a paradigm for designing alloys stabilized via hierarchical nanostructure,achieving good strength-ductility synergy while excellent thermal stability.
基金Project(2009BAE71B00) supported by the National Key Technology R&D Program during the Eleventh Five-Year Plan Period
文摘The microstructures of as-extruded and stabilizing heat-treated Zn-10Al-2Cu-0.02Ti alloys were observed by scanning electron microscopy,transmission electron microscopy,electron probe microanalysis and X-ray diffraction analysis techniques.The change in structure after heat treatment and its effects on room temperature creep behavior were investigated by creep experiments at constant stress and slow strain rate tensile tests.The results show that after stabilizing heat treatment((350℃,30 min,water-cooling)+(100℃,12 h,air-cooling)),the amount of α+η lamellar structure decreases,while the amount of cellular and granular structure increases.The heat-treated Zn-10Al-2Cu-0.02Ti alloy exhibits better creep resistance than the as-extruded alloy,and the rate of steady state creep decreases by 96.9% after stabilizing heat treatment.
文摘A brand new method of automatic north seeking/sight stabilizing is introduced for usage in land fighting vehicles such as tank, etc. Some inertial devices are installed additionally on the platform along with relative control circuits to make its function of North seeking possible. Double position calculation is adopted in this method, and by alignment at two sites the azimuth angle can be figured out. Also the orientation and the horizontal shifts of the gyro are simultaneously measured and compensated so as to improve the accuracy of north seeking. The system can automatically seek north when the vehicle is immobile. And the time consumption is no more than 5.5 min. Besides, the system can keep azimuth angle and provide tilt angle and pitch angle of the vehicle.
基金Project supported by the National Natural Science Foundation of China (No. 40972187)the Key Innovation Team Support Project of Zhejiang Province (No. 2009R50050)
文摘The bending behavior of double-row stabilizing plies is associated with the constructional time delay(CTD),which can be defined as the time interval between the installations of the front stabilizing pile and the rear stabilizing pile.This paper investigates the effect of CTD on the bending moments of double-row stabilizing piles and a method for determining the optimal CTD is proposed.The stabilizing pile is modeled as a cantilever pile embedded in the Winkler elastic foundation.A triangular distributed earth pressure is assumed on the pile segment in the sliding layer.The front stabilizing pile and the rear stabilizing pile are connected by a beam with pinned joints.The analytical solutions of bending moments on the front and the rear stabilizing piles are derived and the accuracy of bending moment solutions is validated by comparing the tensile strain measured from the Hongyan landslide project,Taizhou,Zhejiang,China.It is concluded that CTD has a significant influence on the bending moments of double-row stabilizing piles.An optimal CTD can be obtained when the maximum tensile stress in the front stabilizing pile is equal to that in the rear stabilizing pile,which is 1.4 months for the Hongyan landslide project.
文摘A new technique was introduced for sand stabilization and re-vegetation by use of lignin sand stabilizing material(LSSM). LSSM is a reconstructed organic compound with lignin as the most dominant component from the extracts of black-liquor issued by straw pulp paper mills. Unlike the polyvinyl acetate or foamed asphalt commonly used for dune stabilization, the new material is plant-friendly and can be used with virescence actions simultaneously. The field experimental study was conducted since 2001 in China's Northwest Ningxia Hui Autonomous Region and has been proved that LSSM is effective in stabilizing the fugitive dunes, making the arenaceous plants survive and the bare dune vegetative. The advisable solution concentration is 2% and the optimal field spraying quantity is 2 5 L/m^2 The soil nutrients of the stabilized and greened dune, such as organic matter, available phosphorous and total nitrogen are all increased compared with the control treatment, which is certainly helpful to the growth of arenaceous plants. The technique is worthwhile to be popularized because it is provided not only a new method for desertification control but also an outlet for cleaning contaminants issued from the straw paper mills.
基金supported by the DAAD Scholarship (No. 6-24M)the National Natural Science Foundation of China (No. 30770406)Program for New Century Excellent Talents in Universities of China (No. NCET-06-0773)
文摘Plant regrowth capacity and soil protection were investigated using three flooding-tolerant Yangtze River riverside species (Arundinella anomala, Hemartria compressa and Cynodon dactylon). The root and leaf surface growth, the plant regrowth capacity and the mitigation of soil runoff were analyzed using potted plants that were covered with 5, 10 and 18 cm new sediments, respectively. A. anomala reacted most slowly to the recovery from new sediments, while H. compressa had the highest recovery rates. The latter could produce 24 times the initial root length and 41 times its original leaf surface during the growth period of 12 weeks. C. dactyion showed no significant change in growth in relation to the rising sediment thickness, which means that even 18 cm of new sediments were tolerated by C. dactylon. Erosion tests showed that all three plant species can reduce the soil runoff by more than 63%. Compared to other species, A. anomala was less capable of stabilizing new sediments. The soil protecting abilities of H. compressa decreased after more than 10 cm of new sediments. C. dactyion showed the best soil retention compared to the other species examined, since it could reduce the soil runoff up to 87%. Consequently, C. dactylon was found to be significantly better for soil-protection plant species than A. anomala and H. compressa given the conditions at the Three Gorges Reservoir.
基金supported by the National Key R&D Program of China (2017YFC1501304)the National Natural Science Fund of China (No. 41472261)+1 种基金 the Key Technical Project of Shenzhen Science Technology Project (No. JSGG20160331154546471) the Open Fund of State Key Laboratory of Geohazard Prevention and Geoenviroment Protection (Grant No. SKLGP2017K017)
文摘The paper presents an improved plane layout for stabilizing piles based on a proposed piecewise function expression for the irregular driving force. Based on the specific morphological characteristics of a highway landslide, the piecewise function is used to calculate the irregular driving force by dividing the landslide into several sub-areas.Furthermore, the reasonable layout range and pile spacing can be obtained based on the piecewise function expression of the irregular driving force and on relevant research results of the plane layout for stabilizing piles. Therefore, an improved plane layout of stabilizing piles is presented in consideration of a piecewise function expression of the irregular driving force. A highway landslide located in eastern Guizhou Province, China, is analyzed as a case study using the proposed method. The results demonstrate that the theory presented in this paper provides improved economic benefits and can reduce the requirednumber of stabilizing piles by 28.6% compared with the conventional plane layout scheme.
基金Supported by National Natural Science Foundation of China (30130026, U0632005, 30721063)National Basic Research Program of China (973 Program) (2011CB964803)+1 种基金National Laboratory of Medical Molecular Biology grant (2060204)Beijing municipal government grant (YB20081002301)
文摘Objective To investigate whether α-hemoglobin stabilizing protein (AHSP), the α-globin-specific molecular chaperone, is regulated by erythroid transcription factor NF-E2. Methods We established the stable cell line with NF-E2p45 (the larger subunit of NF-E2) short hairpin RNA to silence its expression. Western blot, real-time polymerase chain reaction, and chromatin immunoprecipitation (ChIP) analysis were performed to detect the expression of AHSP, the histone modifications at AHSP gene locus, and the binding of GATA-1 at the AHSP promoter with NF-E2p45 deficiency. ChIP was also carried out in dimethyl sulfoxide (DMSO)-induced DS19 cells and estrogen-induced G1E-ER4 cells to examine NF-E2 binding to the AHSP gene locus and its changes during cell erythroid differentiation. Finally, luciferase assay was applied in HeLa cells transfected with AHSP promoter fragments to examine AHSP promoter activity in the presence of exogenous NF-E2p45. Results We found that AHSP expression was highly dependent on NF-E2p45. NF-E2 bound to the regions across AHSP gene locus in vivo, and the transcription of AHSP was transactivated by exogenous NF-E2p45. In addition, we observed the decrease of H3K4 trimethylation and GATA-1 occupancy at the AHSP gene locus in NF-E2p45-deficient cells. Restoration of GATA-1 in G1E-ER4 cells in turn led to increased DNA binding of NF-E2p45. Conclusion NF-E2 may play an important role in AHSP gene regulation, providing new insights into the molecular mechanisms underlying the erythroid-specific expression of AHSP as well as new possibilities for β-thalassemia treatment.