The climatic and environmental effects of atmospheric aerosols are a hot topic in global science community, and radiative properties of the aerosols are one of the important parameters in assessing climatic change. He...The climatic and environmental effects of atmospheric aerosols are a hot topic in global science community, and radiative properties of the aerosols are one of the important parameters in assessing climatic change. Here we studied the black carbon concentration and absorption coefficient measured with aethalometers, scattering coefficient measured with nephelometers, and single scattering albedo derived at an atmospheric composition watch station in Guangzhou from 2004 to 2007. Our main results are as follows. The data of black carbon concentration and absorption coefficients measured with instruments cannot be directly used until they are measured in parallel with internationally accepted instruments for comparison, calibration, and reduction. After evaluation of the data, the result shows that the monthly mean of BC concentration varies 3.1―14.8 μg·m-3 and the concentration decreases by about 1 μg·m-3 in average over the four years; It is higher in the dry season with a multi-year mean of 8.9 μg/m3 and lower in the rainy season with a multi-year mean of 8.0 μg·m-3; The extreme maximum of monthly mean concentration occurred in December 2004 and extreme minimum in July 2007, and a 4-year mean is 8.4 μg·m-3. It is also shown that monthly mean scattering coefficient derived varies 129 -565 Mm-1, monthly mean absorption coefficient 32-139 Mm-1, and monthly mean single scattering albedo 0.71-0.91, with annual mean values of 0.80, 0.82, 0.79 and 0.84 for 2004, 2005, 2006 and 2007, respectively. Three instruments were used to take simultaneous measurements of BC in PM10, PM2.5, and PM1 and the results showed that PM2.5 took up about 90% of PM10 and PM1 accounted for about 68% of PM2.5, and BC aerosols are mainly present in fine particulates. The variability of BC concentrations is quite consistent between the Nancun station (141 m above sea level) and the Panyu station (13 m above sea level), which are 8 km apart from each other. The concentration in higher altitude station (Panyu) is consistently lower than展开更多
Carpal tunnel syndrome(CTS) is the most commonly diagnosed disabling condition of the upper extremities. It is the most commonly known and prevalent type of peripheral entrapment neuropathy that accounts for about 90%...Carpal tunnel syndrome(CTS) is the most commonly diagnosed disabling condition of the upper extremities. It is the most commonly known and prevalent type of peripheral entrapment neuropathy that accounts for about 90% of all entrapment neuropathies. This review aims to provide an outline of CTS by considering anat-omy, pathophysiology, clinical manifestation, diagnostic modalities and management of this common condition, with an emphasis on the diagnostic imaging evaluation.展开更多
A closed-form analytic solution of two-dimensional scattering and diffraction of plane SH waves by a semi- cylindrical hill with a semi-cylindrical concentric tunnel inside an elastic half-space is presented using the...A closed-form analytic solution of two-dimensional scattering and diffraction of plane SH waves by a semi- cylindrical hill with a semi-cylindrical concentric tunnel inside an elastic half-space is presented using the cylindrical wave functions expansion method.The solution is reduced to solving a set of infinite linear algebraic equations.Fourier expansion theorem with the form of complex exponential function and cosine function is used.Numerical solutions are obtained by truncation of the infinite equations.The accuracy of the presented numerical results is carefully verified.展开更多
This paper presents 2D wave-current interaction model for evaluating nearly horizontal wave-induced currents in the surf-zone and coastal waters.The hydrodynamic model is the two-dimensional depth-averaged nonlinear s...This paper presents 2D wave-current interaction model for evaluating nearly horizontal wave-induced currents in the surf-zone and coastal waters.The hydrodynamic model is the two-dimensional depth-averaged nonlinear shallow water equations by using an unstructured non-staggered and multiple-level quadtree rectangular mesh,this mesh information is stored in simple data structures and it is easy to obtain a locally high resolution for important region.The intercell fluxes are computed based on the HLL(Harten-Lax-van Leer) approximate Riemann solver with shock capturing capability for computing the dry-to-wet interface of coastal line.The effects of pressure and gravity are included in source term in the model,this treatment can simplify the computation and eliminate numerical imbalance between source and flux terms.The wave model readily provides the radiation stresses that represent the shortwave-averaged forces in a water column for the hydrodynamic model and the wave model takes into account the effect of wave-induced nearshore currents and water level.The coupling model is applied to verify different experimental cases and real life case of considering the wave-current interaction.The calculated results agree with analytical solution,experimental and field data.The results show that the modeling approach presented herein should be useful in simulating the nearshore processes in complicated natural coastal domains.展开更多
This research demonstrates the production of mesoporous activated carbon from sargassum fusiforme via physical activation with carbon dioxide.Central composite design was applied to conduct the experiments at differen...This research demonstrates the production of mesoporous activated carbon from sargassum fusiforme via physical activation with carbon dioxide.Central composite design was applied to conduct the experiments at different levels by altering three operating parameters.Activation temperature(766-934℃),CO2 flow rate(0.8-2.8 L·min^-1)and activation time(5-55 min)were the variables examined in this study.The effect of parameters on the specific surface area,total pore volume and burn-out rate of activated carbon was studied,and the influential parameters of methylene blue adsorption value were identified employing analysis of variance.The optimum conditions for maximum methylene blue adsorption value were:activation temperature=900℃,activation time=29.05 min and CO2 flow rate=1.8 L·min(-1).The activated carbon produced under optimum conditions was characterized by BET,FTIR and SEM.The adsorption behavior on congo red was studied.The effect of parameters on the adsorbent dosage,temperature,PH and initial congo red concentration was investigated.The adsorption properties of the activated carbon were investigated by kinetics.The equilibrium removal rate and maximum adsorption capacity reaches up to 94.72%,234 mg·g^-1,respectively when initial congo red concentration is 200 mg·L^-1 under adsorbent dosage(0.8 g·L^-1),temperature(30℃),PH7.展开更多
Copper （Cu） contamination in the environment has been increased during the years with agricultural and industrial activities. Biotechnological approaches are needed for bioremediation in these areas. The aims of thi...Copper （Cu） contamination in the environment has been increased during the years with agricultural and industrial activities. Biotechnological approaches are needed for bioremediation in these areas. The aims of this study were i） to evaluate the phytoreme- diation capacity of the high-yielding bioenergy plant castor bean （Ricinus communis L.） in vineyard soils （Inceptisol and Mollisol） contaminated with Cu and a Cu mining waste; ii） to characterize the castor bean as a Cu phytoremediation plant; and iii） to evaluate the nutrient uptake by castor bean. Castor bean plants cultivated in soil with toxic levels of Cu for 57 d exhibited high phytomass production, a high tolerance index of roots＇ fresh mass and shoots＇ dry mass, a high level of Cu phytoaccumulation in the roots and also, a robust capacity for Cu phytostabilization. Furthermore, castor bean plants did not significantly deplete soil nutrients （such as N, P, and Mg） during cultivation. Plants cultivated in Inceptisol, Mollisol and Cu mining waste exhibited a strong potential for Cu phytoaccumulation, with values of 5900, 3 052 and 2805 g ha-1, respectively. In addition, the castor bean＇s elevated phytomass production and strong growth in Cu-contaminated soils indicated a high level of Cu phytoaccumulation and a potential application in biofuels. These findings indicate that the castor bean is a efficient hyperaccumulator of Cu and a potential candidate plant for the phytoremediation of Cu-contaminated soil.展开更多
Haloacetic acids, disinfection byproducts （DBPs） formed during drinking water chlorination process are carcinogens. The efficacy of nanofiltration （NF） was examined for the removal of five regulated haloacetic aci...Haloacetic acids, disinfection byproducts （DBPs） formed during drinking water chlorination process are carcinogens. The efficacy of nanofiltration （NF） was examined for the removal of five regulated haloacetic acids （HAAs）： chloro-, dichloro-, and trichioro-acetic acid （CAA, DCAA, and TCAA）; bromo-, and dibromo-acetic acid （BAA, and DBAA） in synthetic water. NF with the dense negatively charged membrane （ES 10）, is the most efficient in removing HAAs than the loose negatively charged membrane （NTR 7410） and neutral surface membrane （NTR 729HF）, due to the greater electrostatic repulsion （Donan exclusion） and sieve effect. Excellent HAAs removal efficiency of 90%-100% could be obtained even at a low pressure of 1×10^5 Pa with ES 10. Changes in cross-flow velocity did not effect the performance of membranes with a small pore size such as ES 10 and NTR 729HF. The increase in HAAs concentration exhibited the adverse effect on the performance of three membranes by strengthening the concentration polarization, which was the driving force for the diffusion of HAA anions across the membrane.展开更多
At the beginning of the Cenozoic,the atmospheric CO_(2)concentration increased rapidly from~2000 ppmv at 60 Ma to~4600 ppmv at 51 Ma,which is 5–10 times higher than the present value,and then continuous declined from...At the beginning of the Cenozoic,the atmospheric CO_(2)concentration increased rapidly from~2000 ppmv at 60 Ma to~4600 ppmv at 51 Ma,which is 5–10 times higher than the present value,and then continuous declined from~51 to 34 Ma.The cause of this phenomenon is still not well understood.In this study,we demonstrate that the initiation of Cenozoic west Pacific plate subduction,triggered by the hard collision in the Tibetan Plateau,occurred at approximately 51 Ma,coinciding with the tipping point.The water depths of the Pacific subduction zones are mostly below the carbonate compensation depths,while those of the Neo-Tethys were much shallower before the collision and caused far more carbonate subducting.Additionally,more volcanic ashes erupted from the west Pacific subduction zones,which consume CO_(2).The average annual west Pacific volvano eruption is 1.11 km~3,which is higher than previous estimations.The amount of annual CO_(2)absorbed by chemical weathering of additional west Pacific volcanic ashes could be comparable to the silicate weathering by the global river.We propose that the initiation of the western Pacific subduction controlled the long-term reduction of atmospheric CO_(2)concentration.展开更多
Objective To evaluate the efficacy and prognostic factors of allogeneic hematopoietic stem cell transplantation(allo-HSCT)in patients with secondary acute myeloid leukemia(sAML).Methods In this multicenter,retrospecti...Objective To evaluate the efficacy and prognostic factors of allogeneic hematopoietic stem cell transplantation(allo-HSCT)in patients with secondary acute myeloid leukemia(sAML).Methods In this multicenter,retrospective clinical study,adult patients aged≥18 years who underwent allo-HSCT for sAML at four centers of the Zhejiang Hematopoietic Stem Cell Transplantation Collaborative Group from January 2014 to November 2022 were included,and the efficacy and prognostic factors of allo-HSCT were analyzed.Results A total of 95 patients were enrolled;66(69.5%)had myelodysplastic syndrome-acute myeloid leukemia(MDS-AML),4(4.2%)had MDS/MPN-AML,and 25(26.3%)had therapy-related AML(tAML).The 3-year CIR,LFS,and overall survival(OS)rates were 18.6%(95%CI 10.2%-27.0%),70.6%(95%CI 60.8%-80.4%),and 73.3%(95%CI 63.9%-82.7%),respectively.展开更多
Extracellular polymeric substances(EPS)form a stable gel-like structure to combine with water molecules through steric hindrance,making the mechanical dewatering of wastewater sludge considerably difficult.Coagulation...Extracellular polymeric substances(EPS)form a stable gel-like structure to combine with water molecules through steric hindrance,making the mechanical dewatering of wastewater sludge considerably difficult.Coagulation/flocculation has been widely applied in improving the sludge dewatering performance,while sludge properties(organic fraction and solution chemistry conditions)are highly changeable and have important effects on sludge flocculation process.In this work,the alkalinity effects on sludge conditioning with hydroxy-aluminum were comprehensively investigated,and the interaction mechanisms between EPS and hydroxy-aluminum with different speciation were unraveled.The results showed that the effectiveness of hydroxy-aluminum conditioning gradually deteriorated with increase in alkalinity.Meanwhile,the polymeric hydroxy-aluminum(Al 13)and highly polymerized hydroxy-aluminum(Al 30)were hydrolysed and converted into amorphous aluminum hydroxide(Al(OH)3),which changed the flocculation mechanism from charge neutralization and complexing adsorption to hydrogen bond interaction.Additionally,both Al 13 and Al 30 showed higher binding capacity for proteins and polysaccharides in EPS than monomeric aluminum and Al(OH)3.Al 13 and Al 30 coagulation changed the secondary structure of proteins in EPS,which caused a gelation reaction to increase molecular hydrophobicity of proteins and consequently sludge dewaterability.This study provided a guidance for optimizing the hydroxy-aluminum flocculation conditioning of sludge with high solution alkalinity.展开更多
Developing high ionic conducting electrolytes is crucial for applying proton-conducting fuel cell(PCFCs)practically.The cur-rent study investigates the effect of alumina on the structural,morphological,electrical,and ...Developing high ionic conducting electrolytes is crucial for applying proton-conducting fuel cell(PCFCs)practically.The cur-rent study investigates the effect of alumina on the structural,morphological,electrical,and electrochemical properties of CeO_(2).Lattice oxygen vacancies are induced in CeO_(2) by a general doping concept that enables fast ionic conduction at low-temperature ranges(300-500℃)for PCFCs.Rietveld refinement of the X-ray diffraction(XRD)patterns established the pure cubic fluorite structure of Al-doped CeO_(2)(ADC)samples and confirmed Al ions’fruitful integration in the CeO_(2) lattice.The electronic structure of the alumina-doped ceria of the materials(10ADC,20ADC,and 30ADC)has been investigated.As a result,it was found that the best composition of 30ADC-based electrolytes induced maximum lattice oxygen vacancies.The corresponding PCFC exhibited a maximum power output of 923 mW/cm^(2)at 500℃.Moreover,the investigation proves the proton-conducting ability of alumina-doped ceria-based fuel cells by using an oxide ion-blocking layer.展开更多
Many biological surfaces are capable of transporting liquids in a directional manner without energy consumption.Inspired by nature,constructing asymmetric gradient surfaces to achieve desired droplet transport,such as...Many biological surfaces are capable of transporting liquids in a directional manner without energy consumption.Inspired by nature,constructing asymmetric gradient surfaces to achieve desired droplet transport,such as a liquid diode,brings an incredibly valuable and promising area of research with a wide range of applications.Enabled by advances in nano-technology and manufacturing techniques,biomimetics has emerged as a promising avenue for engineering various types of anisotropic material system.Over the past few decades,this approach has yielded significant progressin both fundamental understanding and practical applications.Theoretical studies revealed that the heterogeneous composition and topography mainly govern the wetting mechanisms and dynamics behavior of droplets,including the interdisciplinary aspects of materials,chemistry,and physics.In this review,we provide a concise overview of various biological surfaces that exhibit anisotropic droplet transport.We discussed the theoretical foundations and mechanisms of droplet motion on designed surfaces and reviewed recent research advances in droplet directional transport on designed plane surfaces and Janus membranes.Such liquid-diode materials yield diverse promising applications,involving droplet collection,liquid separation and delivery,functional textiles,and biomedical applications.We also discuss the recent challenges and ongoing approaches to enhance the functionality and application performance of anisotropic materials.展开更多
By using the methods of hydrocarbon generation kinetics and carbon isotope kinetics, combined with geological background of natural gas pool formation, the generation and accumulation of natural gas from Yinan 2 gas p...By using the methods of hydrocarbon generation kinetics and carbon isotope kinetics, combined with geological background of natural gas pool formation, the generation and accumulation of natural gas from Yinan 2 gas pool was studied in Kuqa Depression of the Tarim Basin. Natural gas of Yinan 2 gas pool is mainly derived from Middle and Lower Jurassic coal-bearing source rocks, and generally belongs to long time-accumulated gas. It is suggested that Yinan 2 gas is chiefly accumulated in the last 5 Ma, its Ro ranges from 1.25% to 1.95%, and the loss rate of natural gas is about 25%-30%. This work not only complements and reduces the deficiency of formation model of natural gas pools which traditionally depends on the matching relationships between source rock, reservoir, cap rock, and trap, but also is a useful reference in the study of other gas pools.展开更多
The biomedical literature is a vast and invaluable resource for biomedical research.Integrating knowledge from the literature with biomedical data can help biological studies and the clinical decision-making process.E...The biomedical literature is a vast and invaluable resource for biomedical research.Integrating knowledge from the literature with biomedical data can help biological studies and the clinical decision-making process.Efforts have been made to gather information from the biomedical literature and create biomedical knowledge bases,such as KEGG and Reactome.However,manual curation remains the primary method to retrieve accurate biomedical entities and relationships.Manual curation becomes increasingly challenging and costly as the volume of biomedical publications quickly grows.Fortunately,recent advancements in Artificial Intelligence(AI)technologies offer the potential to automate the process of curating,updating,and integrating knowledge from the literature.Herein,we highlight the AI capabilities to aid in mining knowledge and building the knowledge base from the biomedical literature.展开更多
China has planned and implemented a series of lunar and deep space exploration programs since the first lunar exploration satellite Chang’E-1 launched in 2007.In the future,China has initiated the international lunar...China has planned and implemented a series of lunar and deep space exploration programs since the first lunar exploration satellite Chang’E-1 launched in 2007.In the future,China has initiated the international lunar research station program,which aims to build a shared platform on the Moon jointly with many other countries for long-term and continuous lunar exploration,lunar-based observations and experiments,as well as in-situ resource utilization.In addition,China has also proposed an interstellar express mission to unveil the mysteries of the outer heliosphere,nearby interstellar space,and their interactions.This paper gives a brief introduction to the International Lunar Research Station program and the Interstellar Express mission.展开更多
In the matrix factorization(MF)based collaborative filtering recommendation method,the most critical part is to deal with the interaction between the features of users and items.The mainstream approach is to use the i...In the matrix factorization(MF)based collaborative filtering recommendation method,the most critical part is to deal with the interaction between the features of users and items.The mainstream approach is to use the inner product for MF to describe the user-item relationship.However,as a shallow model,MF has its limitations in describing the relationship between data.In addition,when the size of the data is large,the performance of MF is often poor due to data sparsity and noise.This paper presents a model called PIDC,short for potential interaction data clustering based deep learning recommendation.First,it uses classifiers to filter and cluster recommended items to solve the problem of sparse training data.Second,it combines MF and multi-layer perceptron(MLP)to optimize the prediction effect,and the limitation of inner product on the model expression ability is eliminated.The proposed model PIDC is tested on two datasets.The experimental results show that compared with the existing benchmark algorithm,the model improved the recommendation effect.展开更多
Aliphatic biodegradable polyesters have been the most widely used synthetic polymers for developing biodegradable devices as alternatives for the currently used permanent medical devices.The performances during biodeg...Aliphatic biodegradable polyesters have been the most widely used synthetic polymers for developing biodegradable devices as alternatives for the currently used permanent medical devices.The performances during biodegradation process play crucial roles for final realization of their functions.Because physiological and biochemical environment in vivo significantly affects biodegradation process,large numbers of studies on effects of mechanical loads on the degradation of aliphatic biodegradable polyesters have been launched during last decades.In this review article,we discussed the mechanism of biodegradation and several different mechanical loads that have been reported to affect the biodegradation process.Other physiological and biochemical factors related to mechanical loads were also discussed.The mechanical load could change the conformational strain energy and morphology to weaken the stability of the polymer.Besides,the load and pattern could accelerate the loss of intrinsic mechanical properties of polymers.This indicated that investigations into effects of mechanical loads on the degradation should be indispensable.More combination condition of mechanical loads and multiple factors should be considered in order to keep the degradation rate controllable and evaluate the degradation process in vivo accurately.Only then can the degradable devise achieve the desired effects and further expand the special applications of aliphatic biodegradable polyesters.展开更多
Flood events occurrences and frequencies in the world are of immense worry for the stability of the economy and life safety. Africa continent is the third continent the most negatively affected by the flood events aft...Flood events occurrences and frequencies in the world are of immense worry for the stability of the economy and life safety. Africa continent is the third continent the most negatively affected by the flood events after Asia and Europe. Eastern Africa is the most hit in Africa. However, Africa continent is at the early stage in term of flood forecasting models development and implementation. Very few hydrological models for flood forecasting are available and implemented in Africa for the flood mitigation. And for the majority of the cases, they need to be improved because of the time evolution. Flash flood in Bamako (Mali) has been putting both human life and the economy in jeopardy. Studying this phenomenon, as to propose applicable solutions for its alleviation in Bamako is a great concern. Therefore, it is of upmost importance to know the existing scientific works related to this situation in Mali and elsewhere. The main aim was to point out the various solutions implemented by various local and international institutions, in order to fight against the flood events. Two types of methods are used for the flood events adaptation: the structural and non-structural methods. The structural methods are essentially based on the implementation of the structures like the dams, dykes, levees, etc. The problem of these methods is that they may reduce the volume of water that will inundate the area but are not efficient for the prediction of the coming floods and cannot alert the population with any lead time in advance. The non-structural methods are the one allowing to perform the prediction with acceptable lead time. They used the hydrological rainfall-runoff models and are the widely methods used for the flood adaptation. This review is more accentuated on the various types non-structural methods and their application in African countries in general and West African countries in particular with their strengths and weaknesses. Hydrologiska Byråns Vattenbalansavdelning (HBV), Hydrologic Engineer Center Hydrologic Mode展开更多
Implementing hardware primitives into cryptosystem has become a new trend in electronic community.Memristor,with intrinsic stochastic characteristics including the switching voltages,times and energies,as well as the ...Implementing hardware primitives into cryptosystem has become a new trend in electronic community.Memristor,with intrinsic stochastic characteristics including the switching voltages,times and energies,as well as the fluctuations of the resistance state over time,could be a naturally good entropy source for cryptographic key generation.In this study,based on kinetic Monte Carlo Simula-tion,multiple Artificial Intelligence techniques,as well as kernel density map and time constant analysis,memristive spatiotemporal variability within graphene based conductive bridging RAM(CBRAM)have been synergistically analyzed to verify the inher-ent randomness of the memristive stochasticity.Moreover,the ran-dom number based on hardware primitives passed the Hamming Distance calculation with high randomness and uniqueness,and has been integrated into a Rivest-Shamir-Adleman(RSA)cryptosystem.The security of the holistic cryptosystem relies both the modular arithmetic algorithm and the intrinsic randomness of the hardware primitive(to be more reliable,the random num-ber could be as large as possible,better larger than 2048 bits as NIST suggested).The spatiotemporal-variability-based random number is highly random,physically unpredictable and machinelearningattack resilient,improving the robustness of the entire cryptosystem.展开更多
基金Supported by Natural Science Foundation of China (Grant Nos. U0733004,40375002, 40418008, 40775011)National High Technology R & D Program of China (Grant Nos. 2006AA06A306 and 2006AA06A308)National Basic Research Program of China (Grant No. 2005CB422207)
文摘The climatic and environmental effects of atmospheric aerosols are a hot topic in global science community, and radiative properties of the aerosols are one of the important parameters in assessing climatic change. Here we studied the black carbon concentration and absorption coefficient measured with aethalometers, scattering coefficient measured with nephelometers, and single scattering albedo derived at an atmospheric composition watch station in Guangzhou from 2004 to 2007. Our main results are as follows. The data of black carbon concentration and absorption coefficients measured with instruments cannot be directly used until they are measured in parallel with internationally accepted instruments for comparison, calibration, and reduction. After evaluation of the data, the result shows that the monthly mean of BC concentration varies 3.1―14.8 μg·m-3 and the concentration decreases by about 1 μg·m-3 in average over the four years; It is higher in the dry season with a multi-year mean of 8.9 μg/m3 and lower in the rainy season with a multi-year mean of 8.0 μg·m-3; The extreme maximum of monthly mean concentration occurred in December 2004 and extreme minimum in July 2007, and a 4-year mean is 8.4 μg·m-3. It is also shown that monthly mean scattering coefficient derived varies 129 -565 Mm-1, monthly mean absorption coefficient 32-139 Mm-1, and monthly mean single scattering albedo 0.71-0.91, with annual mean values of 0.80, 0.82, 0.79 and 0.84 for 2004, 2005, 2006 and 2007, respectively. Three instruments were used to take simultaneous measurements of BC in PM10, PM2.5, and PM1 and the results showed that PM2.5 took up about 90% of PM10 and PM1 accounted for about 68% of PM2.5, and BC aerosols are mainly present in fine particulates. The variability of BC concentrations is quite consistent between the Nancun station (141 m above sea level) and the Panyu station (13 m above sea level), which are 8 km apart from each other. The concentration in higher altitude station (Panyu) is consistently lower than
文摘Carpal tunnel syndrome(CTS) is the most commonly diagnosed disabling condition of the upper extremities. It is the most commonly known and prevalent type of peripheral entrapment neuropathy that accounts for about 90% of all entrapment neuropathies. This review aims to provide an outline of CTS by considering anat-omy, pathophysiology, clinical manifestation, diagnostic modalities and management of this common condition, with an emphasis on the diagnostic imaging evaluation.
文摘A closed-form analytic solution of two-dimensional scattering and diffraction of plane SH waves by a semi- cylindrical hill with a semi-cylindrical concentric tunnel inside an elastic half-space is presented using the cylindrical wave functions expansion method.The solution is reduced to solving a set of infinite linear algebraic equations.Fourier expansion theorem with the form of complex exponential function and cosine function is used.Numerical solutions are obtained by truncation of the infinite equations.The accuracy of the presented numerical results is carefully verified.
基金supported by the National Natural Science Foundation of China (Grant No. 50839001)the research grant from Southeast Regional Research Initiative (SERRI,80037)the Coastal Inlets Research Program,ERDC,US Army Corps of Engineers,Vicksburg,MS,USA
文摘This paper presents 2D wave-current interaction model for evaluating nearly horizontal wave-induced currents in the surf-zone and coastal waters.The hydrodynamic model is the two-dimensional depth-averaged nonlinear shallow water equations by using an unstructured non-staggered and multiple-level quadtree rectangular mesh,this mesh information is stored in simple data structures and it is easy to obtain a locally high resolution for important region.The intercell fluxes are computed based on the HLL(Harten-Lax-van Leer) approximate Riemann solver with shock capturing capability for computing the dry-to-wet interface of coastal line.The effects of pressure and gravity are included in source term in the model,this treatment can simplify the computation and eliminate numerical imbalance between source and flux terms.The wave model readily provides the radiation stresses that represent the shortwave-averaged forces in a water column for the hydrodynamic model and the wave model takes into account the effect of wave-induced nearshore currents and water level.The coupling model is applied to verify different experimental cases and real life case of considering the wave-current interaction.The calculated results agree with analytical solution,experimental and field data.The results show that the modeling approach presented herein should be useful in simulating the nearshore processes in complicated natural coastal domains.
基金financially supported by the Zhejiang Provincial Natural Science Foundation of China(LY16B060014)the Program for the Joint Research Fund for Overseas Chinese,Hong Kong and Macao Scholars of National Natural Science Foundation of China(Grant No.21628601)the Innovation and Development of Marine Economy Demonstration。
文摘This research demonstrates the production of mesoporous activated carbon from sargassum fusiforme via physical activation with carbon dioxide.Central composite design was applied to conduct the experiments at different levels by altering three operating parameters.Activation temperature(766-934℃),CO2 flow rate(0.8-2.8 L·min^-1)and activation time(5-55 min)were the variables examined in this study.The effect of parameters on the specific surface area,total pore volume and burn-out rate of activated carbon was studied,and the influential parameters of methylene blue adsorption value were identified employing analysis of variance.The optimum conditions for maximum methylene blue adsorption value were:activation temperature=900℃,activation time=29.05 min and CO2 flow rate=1.8 L·min(-1).The activated carbon produced under optimum conditions was characterized by BET,FTIR and SEM.The adsorption behavior on congo red was studied.The effect of parameters on the adsorbent dosage,temperature,PH and initial congo red concentration was investigated.The adsorption properties of the activated carbon were investigated by kinetics.The equilibrium removal rate and maximum adsorption capacity reaches up to 94.72%,234 mg·g^-1,respectively when initial congo red concentration is 200 mg·L^-1 under adsorbent dosage(0.8 g·L^-1),temperature(30℃),PH7.
基金Supported by the Coordenao de Aperfeic oamento de Pessoal de N'vel Superior (CAPES) of Brazil and the Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) of Brazil
文摘Copper （Cu） contamination in the environment has been increased during the years with agricultural and industrial activities. Biotechnological approaches are needed for bioremediation in these areas. The aims of this study were i） to evaluate the phytoreme- diation capacity of the high-yielding bioenergy plant castor bean （Ricinus communis L.） in vineyard soils （Inceptisol and Mollisol） contaminated with Cu and a Cu mining waste; ii） to characterize the castor bean as a Cu phytoremediation plant; and iii） to evaluate the nutrient uptake by castor bean. Castor bean plants cultivated in soil with toxic levels of Cu for 57 d exhibited high phytomass production, a high tolerance index of roots＇ fresh mass and shoots＇ dry mass, a high level of Cu phytoaccumulation in the roots and also, a robust capacity for Cu phytostabilization. Furthermore, castor bean plants did not significantly deplete soil nutrients （such as N, P, and Mg） during cultivation. Plants cultivated in Inceptisol, Mollisol and Cu mining waste exhibited a strong potential for Cu phytoaccumulation, with values of 5900, 3 052 and 2805 g ha-1, respectively. In addition, the castor bean＇s elevated phytomass production and strong growth in Cu-contaminated soils indicated a high level of Cu phytoaccumulation and a potential application in biofuels. These findings indicate that the castor bean is a efficient hyperaccumulator of Cu and a potential candidate plant for the phytoremediation of Cu-contaminated soil.
基金The authors gratefully acknowledge the financial support from National Natural Science Foundation of China （Nos. 21625206, 21632009, 21572258, 21572259, 21421002, 21772098） and the Strategic Priority Research Program of the Chinese Academy of Sciences （No. XDB20000000） for financial support.
基金supported by the National Center of Excellence for Environmental and Hazardous Waste Man- agement (NC-EHWM).
文摘Haloacetic acids, disinfection byproducts （DBPs） formed during drinking water chlorination process are carcinogens. The efficacy of nanofiltration （NF） was examined for the removal of five regulated haloacetic acids （HAAs）： chloro-, dichloro-, and trichioro-acetic acid （CAA, DCAA, and TCAA）; bromo-, and dibromo-acetic acid （BAA, and DBAA） in synthetic water. NF with the dense negatively charged membrane （ES 10）, is the most efficient in removing HAAs than the loose negatively charged membrane （NTR 7410） and neutral surface membrane （NTR 729HF）, due to the greater electrostatic repulsion （Donan exclusion） and sieve effect. Excellent HAAs removal efficiency of 90%-100% could be obtained even at a low pressure of 1×10^5 Pa with ES 10. Changes in cross-flow velocity did not effect the performance of membranes with a small pore size such as ES 10 and NTR 729HF. The increase in HAAs concentration exhibited the adverse effect on the performance of three membranes by strengthening the concentration polarization, which was the driving force for the diffusion of HAA anions across the membrane.
基金supported by NSFC Major Research Plan on‘‘West-Pacific Earth System Multispheric Interactions’’to Prof.Weidong Sun(Grant No.92258303)AND Prof.Tianyu Chen(Grant No.91858105)。
文摘At the beginning of the Cenozoic,the atmospheric CO_(2)concentration increased rapidly from~2000 ppmv at 60 Ma to~4600 ppmv at 51 Ma,which is 5–10 times higher than the present value,and then continuous declined from~51 to 34 Ma.The cause of this phenomenon is still not well understood.In this study,we demonstrate that the initiation of Cenozoic west Pacific plate subduction,triggered by the hard collision in the Tibetan Plateau,occurred at approximately 51 Ma,coinciding with the tipping point.The water depths of the Pacific subduction zones are mostly below the carbonate compensation depths,while those of the Neo-Tethys were much shallower before the collision and caused far more carbonate subducting.Additionally,more volcanic ashes erupted from the west Pacific subduction zones,which consume CO_(2).The average annual west Pacific volvano eruption is 1.11 km~3,which is higher than previous estimations.The amount of annual CO_(2)absorbed by chemical weathering of additional west Pacific volcanic ashes could be comparable to the silicate weathering by the global river.We propose that the initiation of the western Pacific subduction controlled the long-term reduction of atmospheric CO_(2)concentration.
文摘Objective To evaluate the efficacy and prognostic factors of allogeneic hematopoietic stem cell transplantation(allo-HSCT)in patients with secondary acute myeloid leukemia(sAML).Methods In this multicenter,retrospective clinical study,adult patients aged≥18 years who underwent allo-HSCT for sAML at four centers of the Zhejiang Hematopoietic Stem Cell Transplantation Collaborative Group from January 2014 to November 2022 were included,and the efficacy and prognostic factors of allo-HSCT were analyzed.Results A total of 95 patients were enrolled;66(69.5%)had myelodysplastic syndrome-acute myeloid leukemia(MDS-AML),4(4.2%)had MDS/MPN-AML,and 25(26.3%)had therapy-related AML(tAML).The 3-year CIR,LFS,and overall survival(OS)rates were 18.6%(95%CI 10.2%-27.0%),70.6%(95%CI 60.8%-80.4%),and 73.3%(95%CI 63.9%-82.7%),respectively.
基金the National Natural Science Foundation of China(Nos.51678546 and 41630318)the Chinese Universities Scientific Fund of China University of Geosciences(Wuhan)the Major Science and Technology Program for Water Pollution Control and Treatment(No.2018 ZX 07110004)。
文摘Extracellular polymeric substances(EPS)form a stable gel-like structure to combine with water molecules through steric hindrance,making the mechanical dewatering of wastewater sludge considerably difficult.Coagulation/flocculation has been widely applied in improving the sludge dewatering performance,while sludge properties(organic fraction and solution chemistry conditions)are highly changeable and have important effects on sludge flocculation process.In this work,the alkalinity effects on sludge conditioning with hydroxy-aluminum were comprehensively investigated,and the interaction mechanisms between EPS and hydroxy-aluminum with different speciation were unraveled.The results showed that the effectiveness of hydroxy-aluminum conditioning gradually deteriorated with increase in alkalinity.Meanwhile,the polymeric hydroxy-aluminum(Al 13)and highly polymerized hydroxy-aluminum(Al 30)were hydrolysed and converted into amorphous aluminum hydroxide(Al(OH)3),which changed the flocculation mechanism from charge neutralization and complexing adsorption to hydrogen bond interaction.Additionally,both Al 13 and Al 30 showed higher binding capacity for proteins and polysaccharides in EPS than monomeric aluminum and Al(OH)3.Al 13 and Al 30 coagulation changed the secondary structure of proteins in EPS,which caused a gelation reaction to increase molecular hydrophobicity of proteins and consequently sludge dewaterability.This study provided a guidance for optimizing the hydroxy-aluminum flocculation conditioning of sludge with high solution alkalinity.
基金supported by the National Natural Science Foundation of China(Nos.51772080 and 11604088)the Funding from Science and Technology Department of Jiangsu Province,China(No.BE2022029)+1 种基金the Beijing Natural Science Foundation,China(No.IS23050)Prof.Asghar also thanks the Academy of Finland(Nos.13322738 and 13352669)for the financial support.
文摘Developing high ionic conducting electrolytes is crucial for applying proton-conducting fuel cell(PCFCs)practically.The cur-rent study investigates the effect of alumina on the structural,morphological,electrical,and electrochemical properties of CeO_(2).Lattice oxygen vacancies are induced in CeO_(2) by a general doping concept that enables fast ionic conduction at low-temperature ranges(300-500℃)for PCFCs.Rietveld refinement of the X-ray diffraction(XRD)patterns established the pure cubic fluorite structure of Al-doped CeO_(2)(ADC)samples and confirmed Al ions’fruitful integration in the CeO_(2) lattice.The electronic structure of the alumina-doped ceria of the materials(10ADC,20ADC,and 30ADC)has been investigated.As a result,it was found that the best composition of 30ADC-based electrolytes induced maximum lattice oxygen vacancies.The corresponding PCFC exhibited a maximum power output of 923 mW/cm^(2)at 500℃.Moreover,the investigation proves the proton-conducting ability of alumina-doped ceria-based fuel cells by using an oxide ion-blocking layer.
基金National Natural Scienoe Foundation of China(NSFC)(22105012,21975007,22175007,52172080)Bejing Natural Science Foundation(2232054)+2 种基金National Natural Science Foundation of China for Outstanding Youth Foun-dationFundamental Research Funds for the Central Universities,the National Program for Support of Top notch Young Professionals,the 111 Project(grant no.B14009)the open project of the Key Laboratory of Photochemical Conversion and Optoelectronic Mate rials,Technical Institute of Physics and Chemistry,Chinese Academy of Sciences.
文摘Many biological surfaces are capable of transporting liquids in a directional manner without energy consumption.Inspired by nature,constructing asymmetric gradient surfaces to achieve desired droplet transport,such as a liquid diode,brings an incredibly valuable and promising area of research with a wide range of applications.Enabled by advances in nano-technology and manufacturing techniques,biomimetics has emerged as a promising avenue for engineering various types of anisotropic material system.Over the past few decades,this approach has yielded significant progressin both fundamental understanding and practical applications.Theoretical studies revealed that the heterogeneous composition and topography mainly govern the wetting mechanisms and dynamics behavior of droplets,including the interdisciplinary aspects of materials,chemistry,and physics.In this review,we provide a concise overview of various biological surfaces that exhibit anisotropic droplet transport.We discussed the theoretical foundations and mechanisms of droplet motion on designed surfaces and reviewed recent research advances in droplet directional transport on designed plane surfaces and Janus membranes.Such liquid-diode materials yield diverse promising applications,involving droplet collection,liquid separation and delivery,functional textiles,and biomedical applications.We also discuss the recent challenges and ongoing approaches to enhance the functionality and application performance of anisotropic materials.
文摘By using the methods of hydrocarbon generation kinetics and carbon isotope kinetics, combined with geological background of natural gas pool formation, the generation and accumulation of natural gas from Yinan 2 gas pool was studied in Kuqa Depression of the Tarim Basin. Natural gas of Yinan 2 gas pool is mainly derived from Middle and Lower Jurassic coal-bearing source rocks, and generally belongs to long time-accumulated gas. It is suggested that Yinan 2 gas is chiefly accumulated in the last 5 Ma, its Ro ranges from 1.25% to 1.95%, and the loss rate of natural gas is about 25%-30%. This work not only complements and reduces the deficiency of formation model of natural gas pools which traditionally depends on the matching relationships between source rock, reservoir, cap rock, and trap, but also is a useful reference in the study of other gas pools.
基金the National Library of Medicine of the National Institute of Health(NIH)award number 5R01LM013392。
文摘The biomedical literature is a vast and invaluable resource for biomedical research.Integrating knowledge from the literature with biomedical data can help biological studies and the clinical decision-making process.Efforts have been made to gather information from the biomedical literature and create biomedical knowledge bases,such as KEGG and Reactome.However,manual curation remains the primary method to retrieve accurate biomedical entities and relationships.Manual curation becomes increasingly challenging and costly as the volume of biomedical publications quickly grows.Fortunately,recent advancements in Artificial Intelligence(AI)technologies offer the potential to automate the process of curating,updating,and integrating knowledge from the literature.Herein,we highlight the AI capabilities to aid in mining knowledge and building the knowledge base from the biomedical literature.
基金Supported by National Key Research and Development Program of China(2020YFE0202100)。
文摘China has planned and implemented a series of lunar and deep space exploration programs since the first lunar exploration satellite Chang’E-1 launched in 2007.In the future,China has initiated the international lunar research station program,which aims to build a shared platform on the Moon jointly with many other countries for long-term and continuous lunar exploration,lunar-based observations and experiments,as well as in-situ resource utilization.In addition,China has also proposed an interstellar express mission to unveil the mysteries of the outer heliosphere,nearby interstellar space,and their interactions.This paper gives a brief introduction to the International Lunar Research Station program and the Interstellar Express mission.
基金the National Key Research and Development Program of China(2017YFB1401300,2017YFB1401301)the National Natural Science Foundation of China(61902194)+2 种基金the Outstanding Youth of Jiangsu Natural Science Foundation(BK20170100)the Key Research and Development Program of Jiangsu(BE2017166)the Natural Science Foundation of the Jiangsu Higher Education Institutions of China(19KJB520046)。
文摘In the matrix factorization(MF)based collaborative filtering recommendation method,the most critical part is to deal with the interaction between the features of users and items.The mainstream approach is to use the inner product for MF to describe the user-item relationship.However,as a shallow model,MF has its limitations in describing the relationship between data.In addition,when the size of the data is large,the performance of MF is often poor due to data sparsity and noise.This paper presents a model called PIDC,short for potential interaction data clustering based deep learning recommendation.First,it uses classifiers to filter and cluster recommended items to solve the problem of sparse training data.Second,it combines MF and multi-layer perceptron(MLP)to optimize the prediction effect,and the limitation of inner product on the model expression ability is eliminated.The proposed model PIDC is tested on two datasets.The experimental results show that compared with the existing benchmark algorithm,the model improved the recommendation effect.
基金This work was supported by the National Key Technology R&D Program(Nos.2014BAI11B02,2014BAI11B03,2012BAI18B01)National Natural Science Foundation of China(Nos.11120101001,11421202,31370959,11572029,31470915)+3 种基金National key research and development program in China(No.2016YFC1100704,2016YFC1102202,2016YFC1101100)Beijing Nova Programme Interdisciplinary Cooperation Project(No.xxjc201616)Key Laboratory of Advanced Materials of Ministry of Education of China(Tsinghua University),Fok Ying Tung Education Foundation(No.141039)International Joint Research Center of Aerospace Biotechnology and Medical Engineering,Ministry of Science and Technology of China,and the 111 Project(No.B13003).
文摘Aliphatic biodegradable polyesters have been the most widely used synthetic polymers for developing biodegradable devices as alternatives for the currently used permanent medical devices.The performances during biodegradation process play crucial roles for final realization of their functions.Because physiological and biochemical environment in vivo significantly affects biodegradation process,large numbers of studies on effects of mechanical loads on the degradation of aliphatic biodegradable polyesters have been launched during last decades.In this review article,we discussed the mechanism of biodegradation and several different mechanical loads that have been reported to affect the biodegradation process.Other physiological and biochemical factors related to mechanical loads were also discussed.The mechanical load could change the conformational strain energy and morphology to weaken the stability of the polymer.Besides,the load and pattern could accelerate the loss of intrinsic mechanical properties of polymers.This indicated that investigations into effects of mechanical loads on the degradation should be indispensable.More combination condition of mechanical loads and multiple factors should be considered in order to keep the degradation rate controllable and evaluate the degradation process in vivo accurately.Only then can the degradable devise achieve the desired effects and further expand the special applications of aliphatic biodegradable polyesters.
文摘Flood events occurrences and frequencies in the world are of immense worry for the stability of the economy and life safety. Africa continent is the third continent the most negatively affected by the flood events after Asia and Europe. Eastern Africa is the most hit in Africa. However, Africa continent is at the early stage in term of flood forecasting models development and implementation. Very few hydrological models for flood forecasting are available and implemented in Africa for the flood mitigation. And for the majority of the cases, they need to be improved because of the time evolution. Flash flood in Bamako (Mali) has been putting both human life and the economy in jeopardy. Studying this phenomenon, as to propose applicable solutions for its alleviation in Bamako is a great concern. Therefore, it is of upmost importance to know the existing scientific works related to this situation in Mali and elsewhere. The main aim was to point out the various solutions implemented by various local and international institutions, in order to fight against the flood events. Two types of methods are used for the flood events adaptation: the structural and non-structural methods. The structural methods are essentially based on the implementation of the structures like the dams, dykes, levees, etc. The problem of these methods is that they may reduce the volume of water that will inundate the area but are not efficient for the prediction of the coming floods and cannot alert the population with any lead time in advance. The non-structural methods are the one allowing to perform the prediction with acceptable lead time. They used the hydrological rainfall-runoff models and are the widely methods used for the flood adaptation. This review is more accentuated on the various types non-structural methods and their application in African countries in general and West African countries in particular with their strengths and weaknesses. Hydrologiska Byråns Vattenbalansavdelning (HBV), Hydrologic Engineer Center Hydrologic Mode
基金This study was supported by grants from National Nat-ural Science Foundation of China(62174008)Beijing Municipal Education Commission(KZ202110005001)+1 种基金the Ministry of Science and Technology,Taiwan,China(MOST 111-2119-M-492-002-MBK,MOST 111-2622-8-182-001-TS1,MOST 109-2221-E-182-013-MY3,and MOST 110-2221-E-182-043-MY3)the Chang Gung Memorial Hospital(CORPD2J0073).
文摘Implementing hardware primitives into cryptosystem has become a new trend in electronic community.Memristor,with intrinsic stochastic characteristics including the switching voltages,times and energies,as well as the fluctuations of the resistance state over time,could be a naturally good entropy source for cryptographic key generation.In this study,based on kinetic Monte Carlo Simula-tion,multiple Artificial Intelligence techniques,as well as kernel density map and time constant analysis,memristive spatiotemporal variability within graphene based conductive bridging RAM(CBRAM)have been synergistically analyzed to verify the inher-ent randomness of the memristive stochasticity.Moreover,the ran-dom number based on hardware primitives passed the Hamming Distance calculation with high randomness and uniqueness,and has been integrated into a Rivest-Shamir-Adleman(RSA)cryptosystem.The security of the holistic cryptosystem relies both the modular arithmetic algorithm and the intrinsic randomness of the hardware primitive(to be more reliable,the random num-ber could be as large as possible,better larger than 2048 bits as NIST suggested).The spatiotemporal-variability-based random number is highly random,physically unpredictable and machinelearningattack resilient,improving the robustness of the entire cryptosystem.
