Aqueous zinc-iodine batteries(AZIBs)have attracted significant attention as the most promising next-generation energy storage technology due to their low cost,inherent safety,and high energy density.However,their prac...Aqueous zinc-iodine batteries(AZIBs)have attracted significant attention as the most promising next-generation energy storage technology due to their low cost,inherent safety,and high energy density.However,their practical application is hindered by the poor electronic conductivity of iodine cathodes and the severe shuttling effect of intermediate polyiodides.Here,we report a novel micropores carbon framework(MCF)synthesized from waste coffee grounds via a facile carbonization-activation process.The resultant MCF features an ultrahigh specific surface area and a high density of micropores,which not only physically confine iodine species to minimize iodine loss but also enhance the electronic conductivity of the composite cathode.Furthermore,biomass-derived heteroatom dopings(nitrogen functionalities)facilitate effective chemical anchoring of polyiodide intermediates,thereby mitigating the shuttle effect.UV–visible spectroscopy and electrochemical kinetic analyses further confirm the rapid transformation and inhibition mechanism of iodine species by MCF.Consequently,the MCF/I_(2)cathode delivers superior specific capacities of 238.3 mA h g^(−1)at 0.2 A g^(−1)and maintains outstanding cycling performance with a capacity retention of 85.2%after 1200 cycles at 1.0 A g^(−1).This work not only provides an important reference for the design of high-performance iodine-host porous carbon materials but also explores new paths for the sustainable,high-value utilization of waste biomass resources.展开更多
'Wild Play Grounds' are the wild places which can attract people to visit.And the 'Wild Play Grounds' are generally the naturally existing places with unique charm,rather than the established tourist a...'Wild Play Grounds' are the wild places which can attract people to visit.And the 'Wild Play Grounds' are generally the naturally existing places with unique charm,rather than the established tourist attractions or scenic spots.There are no formal organizations for the daily management.Both tickets and clear geographical borders can not be found here.In this research,'Carefree Travelling' is an integrated project of tourism resources in Shandong Province promoted in 2007.Because of their particular characteristics,the 'Wild Play Grounds' have a certain relationship with 'Carefree Travelling',and they are the natural resources of 'Carefree Travelling'.The development of 'Wild Play Grounds' is the further exploitation of the 'Carefree Travelling' resources as well as a better expanding of the tourist market.Relying on the 'Wild Play Grounds',it also has many advantages to develop 'Carefree Travelling',and it will bring good economic and social benefits.Local government should play an important role in developing the 'Wild Play Grounds'.展开更多
The conductive polymer composites(CPCs) with highly efficient electromagnetic interference(EMI)shielding effectiveness(SE) are always accompanied with excessive reflectivity, which would cause serious secondary EMI po...The conductive polymer composites(CPCs) with highly efficient electromagnetic interference(EMI)shielding effectiveness(SE) are always accompanied with excessive reflectivity, which would cause serious secondary EMI pollution. In this regard, the significant reduction of EMI reflection of CPCs to alleviate secondary pollution is deemed to be very important. Herein, a promising cyanate ester(CE) based composite was successfully fabricated by compounding carbonized spent coffee grounds(C-SCG) and graphene nanosheets(GNSs) via a facile solution blending followed by a hot-pressing method. Benefiting from the porous structure of C-SCG and the layered structure of GNSs, a three-dimensional(3 D)multi-interface conductive network in the CE was easily constructed. The EMI SE of the resultant 9 wt%C-SCG/CE composite(C9) is 15.38 d B and dramatically enhanced to 31.09 d B with the presence of 3 wt% GNSs. The remarkable enhancement is mainly attributed to the formation of the efficient conductive pathways as well as the well-dispersion of the incorporated fillers. Meanwhile, the absorption-dominated shielding mechanism in the prepared composites gets benefit from the synergistic effect of porous C-SCG and lamellar GNSs, which effectively captures and attenuates electromagnetic waves. These encouraging findings extend the practical applications of porous biocarbon materials in EMI shielding field.展开更多
As the world's population exponentially grows,so does the need for the production of food,with cereal production growing annually from an estimated 1.0 billion to 2.5 billion tons within the last few decades.This ...As the world's population exponentially grows,so does the need for the production of food,with cereal production growing annually from an estimated 1.0 billion to 2.5 billion tons within the last few decades.This rapid growth in food production results in an ever increasing amount of agricultural wastes,of which already occupies nearly 50%of the total landfill area.For example,is the billions of dry tons of cellulose-containing spent coffee grounds disposed in landfills annually.This paper seeks to provide a method for isolating cellulose nanocrystals(CNCs)from spent coffee grounds,in order to recycle and utilize the cellulosic waste material which would otherwise have no applications.CNCs have already been shown to have vast applications in the polymer engineering field,mainly utilized for their high strength to weight ratio for reinforcement of polymer-based nanocomposites.A successful method of purifying and hydrolyzing the spent coffee grounds in order to isolate usable CNCs was established.The CNCs were then characterized using current techniques to determine important chemical and physical properties.A few crucial properties determined were aspect ratio of 12±3,crystallinity of 74.2%,surface charge density of(48.4±6.2)mM/kg cellulose,and the ability to successfully reinforce a polymer based nanocomposite.These characteristics compare well to other literature data and common commercial sources of CNCs.展开更多
The southern continental margin of the South China Sea has documented multiphase continental rifting corresponding to the propagation of seafloor spreading.Here we investigate three multi-channel seismic reflection pr...The southern continental margin of the South China Sea has documented multiphase continental rifting corresponding to the propagation of seafloor spreading.Here we investigate three multi-channel seismic reflection profiles across different segments of the Dangerous Grounds with a NE-SW direction.Stratigraphic correlation reveals that the Cenozoic tectono-stratigraphic framework in the Dangerous Grounds is featured with diachronous rifting,which records the successive spreading of East Subbasin and Southwest Subbasin,South China Sea.By reconstructing the tectono-sedimentary evolution history in different segments,we combine the quantification of the brittle extension,tectonic subsidence,as well as the crustal thinning.Results provide evidence that the extensional stress migrated from northeast to southwest with the progressive propagation of the seafloor spreading in the oceanic basin.Besides,the impact of the tectonic propagation persists even after the cessation of seafloor spreading,evidenced by a longer stretching duration in the West-Dangerous Grounds than that in the eastern area.Moreover,a temporary syn-rift subsidence delay synchronously to the spreading of the adjacent oceanic basin is observed along the southern margin.This observation proves the secondary mantle convection during the seafloor spreading in the southern continental margin,which is related to the propagating rift.展开更多
Researches on tea have been developed for decades, which prove that tea, especially green tea, has multiple functional components. With the rapid development of beverage industry, the resultant large amounts of tea gr...Researches on tea have been developed for decades, which prove that tea, especially green tea, has multiple functional components. With the rapid development of beverage industry, the resultant large amounts of tea grounds attract great attention. However, unreasonable utilization of tea grounds would lead to great waste and environmental pollution, especially in summer. In view of the high nutritive value and multiple functional components, tea grounds could be used as feedstuff. By now, researches of tea grounds as feedstuff are mainly on ruminant, as the utilization on other animals is limited to lower level due to high fiber content. Therefore, the following review will begin with a brief introduction of tea grounds and the possible utilization of tea grounds as feedstuff, and then elaborate on the application of ensiling and total mixed ration on ruminant. Apart from the fermentation quality, nutritive value is also provided to assess feasibilities of using tea grounds as feedstuff resources. Finally, a summary on the utilization situation and future direction of using tea grounds as feedstuff is provided in this review.展开更多
Two predominant currents, the warm Kuroshio Current and the cold Oyashio Current, meet in the North- west Pacific Ocean. The dynamics of physical oceanographic structures in this region, including frontal zones and me...Two predominant currents, the warm Kuroshio Current and the cold Oyashio Current, meet in the North- west Pacific Ocean. The dynamics of physical oceanographic structures in this region, including frontal zones and meandering eddies, result in a highly productive habitat that serves as a favorable feeding ground for various commercially important species. Neon flying squid, Ommastrephes bartramii, is an im- portant oceanic squid, which is widely distributed in the North Pacific Ocean. Based on the catch data col- lected by Chinese squid jigging fleets and relevant environmental data, including sea surface temperature （SST） and fronts （represented by gradients of SST and thermocline） during 1998-2009, the variations of oceanic fronts and their influence on the fishing grounds of O. bartramii were evaluated, and the differ- ences in distribution of fishing grounds of O. bartramii in 2000 and 2002 were compared by describing the differences in vertical temperature between 0-300 m. It was found that the preferred horizontal tem- perature gradient of SST for O. bartramii tended to be centered at 0.01-0.02~C/nm, which attracted nearly 80% of the total fishing effort, and the preferred horizontal temperature gradients at the 50 m and 105 m layers were mainly located at 0.01-0.03~C/nm, which accounted for more than 70% of the total fishing effort during August-October. The preferred vertical temperature gradient within the 0-50 m layer for O. bartramii tended to be centered at 0.15-0.25~C/m during August and September and at 0.10-0.15~C/m in October, implying that the mixed surface layer was distributed at depths of 0-50 m. It was concluded that the vertical temperature gradient was more important than the horizontal temperature gradient in playing a role in forming the fishing ground. The results improved our understanding of the spatial dynamics of the 0. bartramii fishery.展开更多
This study presents an application of artificial neural network(ANN)and Bayesian network(BN)for evaluation of jamming risk of the shielded tunnel boring machines(TBMs)in adverse ground conditions such as squeezing gro...This study presents an application of artificial neural network(ANN)and Bayesian network(BN)for evaluation of jamming risk of the shielded tunnel boring machines(TBMs)in adverse ground conditions such as squeezing grounds.The analysis is based on database of tunneling cases by numerical modeling to evaluate the ground convergence and possibility of machine entrapment.The results of initial numerical analysis were verified in comparison with some case studies.A dataset was established by performing additional numerical modeling of various scenarios based on variation of the most critical parameters affecting shield jamming.This includes compressive strength and deformation modulus of rock mass,tunnel radius,shield length,shield thickness,in situ stresses,depth of over-excavation,and skin friction between shield and rock.Using the dataset,an ANN was trained to predict the contact pressures from a series of ground properties and machine parameters.Furthermore,the continuous and discretized BNs were used to analyze the risk of shield jamming.The results of these two different BN methods are compared to the field observations and summarized in this paper.The developed risk models can estimate the required thrust force in both cases.The BN models can also be used in the cases with incomplete geological and geomechanical properties.展开更多
Spent Coffee Ground (SCG) is characterized by high organic content, in the form of insoluble polysaccharides bound and phenol compounds. Phenol compounds are toxic to nature and <span style="font-family:Verdan...Spent Coffee Ground (SCG) is characterized by high organic content, in the form of insoluble polysaccharides bound and phenol compounds. Phenol compounds are toxic to nature and <span style="font-family:Verdana;">are</span><span style="font-family:Verdana;"> a cause of environmental pollution. Composting method of this study is aerobic static batch composting with temperature control with adding activators of some fungi such as </span><i><span style="font-family:Verdana;">Aspergillus sp</span></i><span style="font-family:Verdana;">, and </span><i><span style="font-family:Verdana;">Penicillium sp. </span></i><span style="font-family:Verdana;">The purpose of the research is to fill the research gap from previous studies of spent coffee grounds compost, which requires a long time in composting, so that if it is used directly on the soil and plants, the positive effect also requires a long time. The result of composting for 28 days with this method is that mature compost has black crumb and normal pH, with characteristics of C/N ratio below 10: C1 (7.06), C2 (6.99). This value is far from the control with a C/N ratio of 8.33. Decompose rate of macromolecule are above 40% for lignin and 70% for cellulose. Implementation of compost in radish plants, resulting Germination Index above 80% which indicates that the compost is ripe: control (92.39%), C1 (183.88%), C2 (191.86%). The results of the analysis with FTIR also showed that the compost was mature and stable, and rich in minerals. So, it can be concluded </span><span style="font-family:Verdana;">that</span><span style="font-family:Verdana;"> this composting method can speed up composting time and optimize the results of compost produced.</span>展开更多
Using the shooting argument and an approximating method, this paper isconcerncd with the existence of fast-decay ground state of p-Laplacian equation: Apu＋f(u)=0, in Rn, where f(u) behaves just like f(u) = uq - us, a...Using the shooting argument and an approximating method, this paper isconcerncd with the existence of fast-decay ground state of p-Laplacian equation: Apu＋f(u)=0, in Rn, where f(u) behaves just like f(u) = uq - us, as s>q>np/(n-p) - 1.展开更多
In this paper, we discussed the influence of the initial tectonic stress on the relative measurement value of the ground stress when a long cylindrical straingauge is used in the viscoelastic media. We simulate the...In this paper, we discussed the influence of the initial tectonic stress on the relative measurement value of the ground stress when a long cylindrical straingauge is used in the viscoelastic media. We simulate the whole system consisting of the stratum, cement ring and the straingauge cylinder with a three layer medium model and obtain the solution of radial displacement on the inner wall of the straingauge under the action of initial tectonic stress by using the correspondence principle. The result showes: 1) The influence of initial stress making of the radial displacement on the inner wall of the straingauge increases gradually with time at a gradually reduced rate and tends to a certain value eventually; 2) The principal stress with a magnitude of [C 0+C 1 exp (- ω 1t)+ C 2 exp(- ω 2t )] σ i0 in the opposite direction of initial stress will be superimposed to the measuring result of stress change without considering the initial stress. where C 0, C 1, C 2 and ω 1, ω 2 are related only to the mechanical property of the stratum, σ i0 (i=1, 2) are the two principal components of the initial tectonic stress. It is pointed out that the initial tectonic stress affects obviously on the measurement of the relative change of ground stress in the cases of soft strata and high initial stress.展开更多
The design procedure is made for a mine shaft where permanent underground facilities are interconnected. The highly faulted grounds were identified using empirical and semi-empirical theories. Furthermore, the behavio...The design procedure is made for a mine shaft where permanent underground facilities are interconnected. The highly faulted grounds were identified using empirical and semi-empirical theories. Furthermore, the behavior types are presented. This paper presents excavation and support methods in such ground conditions and the calculations results show that the installation of the yielding elements have an effect on support elements and prevent shotcrete damage during the curing stage. Different numerical analyses carried out showed that, with the yielding elements installed, the total displacements increase but the final axial force reduces, and therefore, the characteristic compressive strength of shotcrete is not exceeded. The calculation results of ground loads and displacements on the designed support system are presented with a 3D numerical geo-mechanical model adopted for highly faulted ground surrounding deeper complex underground structures.展开更多
The Dangerous Grounds,located in the southern margin of the South China Sea,has experienced three distinct tectonic evolution stages during the Cenozoic:continental rifting,breakup from the South China Block and south...The Dangerous Grounds,located in the southern margin of the South China Sea,has experienced three distinct tectonic evolution stages during the Cenozoic:continental rifting,breakup from the South China Block and southward drift,and collision with Borneo,accompanied by a north-to-south shift in its paleogeographic environment.This study utilized a robust dataset comprising 67 seismic reflection profiles,integrated with drilling and dredging data,to reconstruct the sedimentary filling history of the Dangerous Grounds.By correlating sediment budget outcomes with the spatial distribution characteristics of the sediment thickness,we have gained valuable insights into the region's sedimentary evolution.Our findings reveal a progressive increase in sediment budgets across the three tectonic stages,despite relatively stable sediment budgets during the southward drift stage associated with seafloor spreading.Spatial sediment distribution shows a continued decrease in the east and expansion in the south and west.By integrating the temporal and spatial distribution of depocenters with drilling results and sediment provenance through geochemical analyses,we provide a comprehensive regional perspective on the factors controlling sediment budget trends,including regional tectonic events,monsoon,sea level change,and the river systems associated with paleogeographic environment variations.The sedimentary inputs to the Dangerous Grounds have shifted over time,with Paleocene-Eocene sediments primarily originating from the north.From the Oligocene to the Early Miocene,northern sediment supply progressively declined,while inputs from the southwest,transported through river systems originating in the Indochina and Malay Peninsulas,gradually increased.Since the Mid-Miocene,the collision with Borneo has led to enhanced sediment supply from the south,with sediments predominantly accumulating along slope edges,channel outlets,and within the Nansha Trough.展开更多
This paper reported the facile preparation of pyrolytic carbon derived from spent coffee grounds and the evaluation of its electrochemical performance when used as anode in sodium-ion battery.X-ray diffraction analys...This paper reported the facile preparation of pyrolytic carbon derived from spent coffee grounds and the evaluation of its electrochemical performance when used as anode in sodium-ion battery.X-ray diffraction analysis,scanning electron microscope,Brunauer–Emmett–Teller were employed to characterize the structure of pyrolytic carbon.Electrochemical performances were tested by constant current charge–discharge,cyclic voltammetry and electrochemical impedance spectroscopy.Results showed that the pyrolytic carbon possess a porous structure(1–2 lm)and a specific surface area of 94.35 m2 g1.When used as anodes in sodium-ion batteries,a reversible capacity of 154.2 mA h g1 at a current density of 200 mA g1 after 50 cycles was obtained.Several electrolytes were evaluated and their electrochemical performances were compared.The result indicated that this material has excellent storage capacity and good cycling stability.Our method provided a preparation of pyrolytic carbon from environmentally friendly resources.展开更多
Herein the biowaste by-product spent coffee grounds(SCGs)from coffee industry were incorporated into asphalt binders for performance enhancement.From the analysis of Fourier transform infrared spectroscopy(FTIR),diffe...Herein the biowaste by-product spent coffee grounds(SCGs)from coffee industry were incorporated into asphalt binders for performance enhancement.From the analysis of Fourier transform infrared spectroscopy(FTIR),differential scanning calorimetry(DSC),dynamic shear rheometer(DSR),and Brookfield viscosity rheometer,it is confirmed that SCGs have potential prospects as bio-waste modifiers in the application of sustainable pavements.Results demonstrated that the modification process was mainly based on physical reinforcement.Compared with that of the neat asphalt,the shearing stress-resistant ability and high-temperature performance of the SCGs modified binders with the appropriate addition presented a bit of improvement;whereas the binders with 1%and 3%SCGs exhibited remarkably enhanced low-temperature stability.However,notable weaknesses of practical performance were shown for the binder with excessive content of SCGs,indicating the necessity of proportion selecting before application.展开更多
Outdoor tests are playing a more and more significant role in R & D of automobiles, especially prompt tests done in the proving ground which can extremely shorten the period of development. That is the reason that...Outdoor tests are playing a more and more significant role in R & D of automobiles, especially prompt tests done in the proving ground which can extremely shorten the period of development. That is the reason that four proving ground have been set up in China. They are Hainan Proving Ground, Dongfeng Proving Ground, Dingyuan Proving Ground and Tongxian Proving Ground.展开更多
Genetic screening has its uses:It helped A-list actor Angelina Jolie,for example,determine that she was at a high risk of breast cancer,leading to a preventative mastectomy.But what genetic screening can’t demonstrat...Genetic screening has its uses:It helped A-list actor Angelina Jolie,for example,determine that she was at a high risk of breast cancer,leading to a preventative mastectomy.But what genetic screening can’t demonstrate is whether,broadly speaking,your child will have an aptitude for mathematics or sports.Certain specific health problems,yes;but sweeping statements about the future character of an adult?The scientific evidence for such tests was展开更多
The main use for spent coffee grounds (SCG) produced in the soluble coffee industry is thermal energy generation in the industry itself. The SCG are processed using operations that are strongly dependent on powder flo...The main use for spent coffee grounds (SCG) produced in the soluble coffee industry is thermal energy generation in the industry itself. The SCG are processed using operations that are strongly dependent on powder flow behavior. In this study, we evaluated two classical flowability in dices of non-consolidated SCG powders: the angle of repose (AoR), and the Hausner ratio (HR). The influences of the mean particle diameter, particle size distribution (PSD), and water content on the AoR and HR values of SCG were analyzed for powders with a mean particle size range of 225-550 μm. For powders with a mean particle size close to 350 μm and for mixtures containing more than 40% fine particles, the HR (>1.35) and AoR (>45 °) values were characteristic of poor flowability. The AoR was sensitive to the powder PSD, and powders with similar mean particle sizes had higher AoR values when the PSD was larger. For powders w让h water contents up to 50%, the flowability indices were not greatly affected by the water content. A modified linear-mixture packing model was used to predict the packed bed void fractions for binary and ternary mixtures of the three base powders. The model was used to construct a ternary diagram to estimate the HR values of the mixtures. An equation was fitted to correlate HR and AoR. The proposed diagram and the equation provide insight into flow behavior and could be used for process design of industrial plants that handle SCG.展开更多
EXCERPTS FROM MAJOR CHINESE MAGAZINES RETURN OF THE SAND MARTINS Oriental Outlook 29 May In late April,a sandy cliff along the Yongding River in southern Beijing became an unexpected attraction.Speckled with more than...EXCERPTS FROM MAJOR CHINESE MAGAZINES RETURN OF THE SAND MARTINS Oriental Outlook 29 May In late April,a sandy cliff along the Yongding River in southern Beijing became an unexpected attraction.Speckled with more than 100 nests built by sand martins,migratory birds that return to the city each summer,the site has become one of the largest breeding grounds for the species in the Chinese capital.Just a year ago,this fragile micro-habitat was nearly lost to a river management project.Fortunately,a group of bird-watchers spotted the threat in time and alerted city officials.展开更多
Dispatched by the Chinese government,a multidisciplinary team of 30 researchers collaborated with a team from Myanmar to conduct a 14-day on-site investigation.The work encompassed seismic intensity assessments,field ...Dispatched by the Chinese government,a multidisciplinary team of 30 researchers collaborated with a team from Myanmar to conduct a 14-day on-site investigation.The work encompassed seismic intensity assessments,field surveys,and loss evaluations.The paper focuses on the intensity distribution and structural damage characteristics of the 2025 M7.9 Myanmar earthquake,yielding the following key findings.(1)The seismogenic fault rupture propagated in a nearly N-S direction,with a surface rupture length of approximately 450 km.The seismic impact zone exhibited an elongated N-S distribution and a shorter E-W span,distributed like a belt around the seismogenic fault.(2)Within the seismic impact zones,existing buildings comprised five primary structural types,with timber(bamboo)structures constituting the largest proportion(≈80%in rural areas,≈50%in urban areas).The relatively low disaster losses and casualties were primarily attributable to the good seismic performance and low damage ratio of timber(bamboo)structures across varying intensity zones.(3)An anomalous zone of intensityⅨwas located at the boundary between intensityⅥandⅦregions in Nay Pyi Taw.Here,ridge topography combined with soft soil layers significantly amplified ground motion,exacerbating structural damage.(4)Directional effects of ground motion were observed,with the structural damage phenomena and peak ground acceleration(PGA)values in the N-S direction exceeding those in the E-W direction.This validates that the maximum PGA distribution of strike-slip fault earthquakes aligns with the fault strike.The research is expected to provide technical support for post-disaster reconstruction planning,site selection,and disaster mitigation strategies in Myanmar.展开更多
基金financial support from the National Natural Science Foundation of China(U23B20166,U21A20289)International Joint Doctoral Education Fund of Beihang University,and Open Fund of Key Laboratory of Biodiversity and Environment on the Qinghai-Tibet Plateau,Ministry of Education(KLBE2024001)+7 种基金Australian Research Council(ARC)through the Future Fellowship(FT210100298)Discovery Project(DP220100603)Linkage Project(LP210200504,LP220100088,LP230200897)Industrial Transformation Research Hub(IH240100009)schemesthe Australian Government through the Cooperative Research Centres Projects(CRCPXIII000077)the Australian Renewable Energy Agency(ARENA)part of ARENA’s Transformative Research Accelerating Commercialisation Program(TM021)European Commission’s Australia-Spain Network for Innovation and Research Excellence(AuSpire).
文摘Aqueous zinc-iodine batteries(AZIBs)have attracted significant attention as the most promising next-generation energy storage technology due to their low cost,inherent safety,and high energy density.However,their practical application is hindered by the poor electronic conductivity of iodine cathodes and the severe shuttling effect of intermediate polyiodides.Here,we report a novel micropores carbon framework(MCF)synthesized from waste coffee grounds via a facile carbonization-activation process.The resultant MCF features an ultrahigh specific surface area and a high density of micropores,which not only physically confine iodine species to minimize iodine loss but also enhance the electronic conductivity of the composite cathode.Furthermore,biomass-derived heteroatom dopings(nitrogen functionalities)facilitate effective chemical anchoring of polyiodide intermediates,thereby mitigating the shuttle effect.UV–visible spectroscopy and electrochemical kinetic analyses further confirm the rapid transformation and inhibition mechanism of iodine species by MCF.Consequently,the MCF/I_(2)cathode delivers superior specific capacities of 238.3 mA h g^(−1)at 0.2 A g^(−1)and maintains outstanding cycling performance with a capacity retention of 85.2%after 1200 cycles at 1.0 A g^(−1).This work not only provides an important reference for the design of high-performance iodine-host porous carbon materials but also explores new paths for the sustainable,high-value utilization of waste biomass resources.
文摘'Wild Play Grounds' are the wild places which can attract people to visit.And the 'Wild Play Grounds' are generally the naturally existing places with unique charm,rather than the established tourist attractions or scenic spots.There are no formal organizations for the daily management.Both tickets and clear geographical borders can not be found here.In this research,'Carefree Travelling' is an integrated project of tourism resources in Shandong Province promoted in 2007.Because of their particular characteristics,the 'Wild Play Grounds' have a certain relationship with 'Carefree Travelling',and they are the natural resources of 'Carefree Travelling'.The development of 'Wild Play Grounds' is the further exploitation of the 'Carefree Travelling' resources as well as a better expanding of the tourist market.Relying on the 'Wild Play Grounds',it also has many advantages to develop 'Carefree Travelling',and it will bring good economic and social benefits.Local government should play an important role in developing the 'Wild Play Grounds'.
基金financial support from the National Natural Science Foundation of China (No. 51773167)the Natural Science Foundation of Shaanxi Province (No. 2019CGXNG-033)+2 种基金the Science and Technology Plan Project of Xi’an (Nos. 2019217814GXRC014CG015-GXYD14.7, and 2019217814GXRC014CG015-GXYD14.8)the China Postdoctoral Science Foundation (No. 2019M650268)the Opening Project of State Key Laboratory of Polymer Materials Engineering (Sichuan University) (No. sklpme2020-4-16)。
文摘The conductive polymer composites(CPCs) with highly efficient electromagnetic interference(EMI)shielding effectiveness(SE) are always accompanied with excessive reflectivity, which would cause serious secondary EMI pollution. In this regard, the significant reduction of EMI reflection of CPCs to alleviate secondary pollution is deemed to be very important. Herein, a promising cyanate ester(CE) based composite was successfully fabricated by compounding carbonized spent coffee grounds(C-SCG) and graphene nanosheets(GNSs) via a facile solution blending followed by a hot-pressing method. Benefiting from the porous structure of C-SCG and the layered structure of GNSs, a three-dimensional(3 D)multi-interface conductive network in the CE was easily constructed. The EMI SE of the resultant 9 wt%C-SCG/CE composite(C9) is 15.38 d B and dramatically enhanced to 31.09 d B with the presence of 3 wt% GNSs. The remarkable enhancement is mainly attributed to the formation of the efficient conductive pathways as well as the well-dispersion of the incorporated fillers. Meanwhile, the absorption-dominated shielding mechanism in the prepared composites gets benefit from the synergistic effect of porous C-SCG and lamellar GNSs, which effectively captures and attenuates electromagnetic waves. These encouraging findings extend the practical applications of porous biocarbon materials in EMI shielding field.
文摘As the world's population exponentially grows,so does the need for the production of food,with cereal production growing annually from an estimated 1.0 billion to 2.5 billion tons within the last few decades.This rapid growth in food production results in an ever increasing amount of agricultural wastes,of which already occupies nearly 50%of the total landfill area.For example,is the billions of dry tons of cellulose-containing spent coffee grounds disposed in landfills annually.This paper seeks to provide a method for isolating cellulose nanocrystals(CNCs)from spent coffee grounds,in order to recycle and utilize the cellulosic waste material which would otherwise have no applications.CNCs have already been shown to have vast applications in the polymer engineering field,mainly utilized for their high strength to weight ratio for reinforcement of polymer-based nanocomposites.A successful method of purifying and hydrolyzing the spent coffee grounds in order to isolate usable CNCs was established.The CNCs were then characterized using current techniques to determine important chemical and physical properties.A few crucial properties determined were aspect ratio of 12±3,crystallinity of 74.2%,surface charge density of(48.4±6.2)mM/kg cellulose,and the ability to successfully reinforce a polymer based nanocomposite.These characteristics compare well to other literature data and common commercial sources of CNCs.
基金financially supported by the Open Fund of Hubei Key Laboratory of Marine Geological Resources(No.MGR202004)the National Natural Science Foundation of China(Nos.41890811,41676027,41906070)。
文摘The southern continental margin of the South China Sea has documented multiphase continental rifting corresponding to the propagation of seafloor spreading.Here we investigate three multi-channel seismic reflection profiles across different segments of the Dangerous Grounds with a NE-SW direction.Stratigraphic correlation reveals that the Cenozoic tectono-stratigraphic framework in the Dangerous Grounds is featured with diachronous rifting,which records the successive spreading of East Subbasin and Southwest Subbasin,South China Sea.By reconstructing the tectono-sedimentary evolution history in different segments,we combine the quantification of the brittle extension,tectonic subsidence,as well as the crustal thinning.Results provide evidence that the extensional stress migrated from northeast to southwest with the progressive propagation of the seafloor spreading in the oceanic basin.Besides,the impact of the tectonic propagation persists even after the cessation of seafloor spreading,evidenced by a longer stretching duration in the West-Dangerous Grounds than that in the eastern area.Moreover,a temporary syn-rift subsidence delay synchronously to the spreading of the adjacent oceanic basin is observed along the southern margin.This observation proves the secondary mantle convection during the seafloor spreading in the southern continental margin,which is related to the propagating rift.
文摘Researches on tea have been developed for decades, which prove that tea, especially green tea, has multiple functional components. With the rapid development of beverage industry, the resultant large amounts of tea grounds attract great attention. However, unreasonable utilization of tea grounds would lead to great waste and environmental pollution, especially in summer. In view of the high nutritive value and multiple functional components, tea grounds could be used as feedstuff. By now, researches of tea grounds as feedstuff are mainly on ruminant, as the utilization on other animals is limited to lower level due to high fiber content. Therefore, the following review will begin with a brief introduction of tea grounds and the possible utilization of tea grounds as feedstuff, and then elaborate on the application of ensiling and total mixed ration on ruminant. Apart from the fermentation quality, nutritive value is also provided to assess feasibilities of using tea grounds as feedstuff resources. Finally, a summary on the utilization situation and future direction of using tea grounds as feedstuff is provided in this review.
基金The National High-Tech R&D Program of China(863 Program)under contract Nos 2012AA092301 and 2012AA092303the Project of Shanghai Science and Technology Innovation under contract No.12231203900+1 种基金the Industrialization Program of National Development and Reform Commission under contract No.2159999the Shanghai Universities First-class Disciplines Project(Fisheries)"
文摘Two predominant currents, the warm Kuroshio Current and the cold Oyashio Current, meet in the North- west Pacific Ocean. The dynamics of physical oceanographic structures in this region, including frontal zones and meandering eddies, result in a highly productive habitat that serves as a favorable feeding ground for various commercially important species. Neon flying squid, Ommastrephes bartramii, is an im- portant oceanic squid, which is widely distributed in the North Pacific Ocean. Based on the catch data col- lected by Chinese squid jigging fleets and relevant environmental data, including sea surface temperature （SST） and fronts （represented by gradients of SST and thermocline） during 1998-2009, the variations of oceanic fronts and their influence on the fishing grounds of O. bartramii were evaluated, and the differ- ences in distribution of fishing grounds of O. bartramii in 2000 and 2002 were compared by describing the differences in vertical temperature between 0-300 m. It was found that the preferred horizontal tem- perature gradient of SST for O. bartramii tended to be centered at 0.01-0.02~C/nm, which attracted nearly 80% of the total fishing effort, and the preferred horizontal temperature gradients at the 50 m and 105 m layers were mainly located at 0.01-0.03~C/nm, which accounted for more than 70% of the total fishing effort during August-October. The preferred vertical temperature gradient within the 0-50 m layer for O. bartramii tended to be centered at 0.15-0.25~C/m during August and September and at 0.10-0.15~C/m in October, implying that the mixed surface layer was distributed at depths of 0-50 m. It was concluded that the vertical temperature gradient was more important than the horizontal temperature gradient in playing a role in forming the fishing ground. The results improved our understanding of the spatial dynamics of the 0. bartramii fishery.
文摘This study presents an application of artificial neural network(ANN)and Bayesian network(BN)for evaluation of jamming risk of the shielded tunnel boring machines(TBMs)in adverse ground conditions such as squeezing grounds.The analysis is based on database of tunneling cases by numerical modeling to evaluate the ground convergence and possibility of machine entrapment.The results of initial numerical analysis were verified in comparison with some case studies.A dataset was established by performing additional numerical modeling of various scenarios based on variation of the most critical parameters affecting shield jamming.This includes compressive strength and deformation modulus of rock mass,tunnel radius,shield length,shield thickness,in situ stresses,depth of over-excavation,and skin friction between shield and rock.Using the dataset,an ANN was trained to predict the contact pressures from a series of ground properties and machine parameters.Furthermore,the continuous and discretized BNs were used to analyze the risk of shield jamming.The results of these two different BN methods are compared to the field observations and summarized in this paper.The developed risk models can estimate the required thrust force in both cases.The BN models can also be used in the cases with incomplete geological and geomechanical properties.
文摘Spent Coffee Ground (SCG) is characterized by high organic content, in the form of insoluble polysaccharides bound and phenol compounds. Phenol compounds are toxic to nature and <span style="font-family:Verdana;">are</span><span style="font-family:Verdana;"> a cause of environmental pollution. Composting method of this study is aerobic static batch composting with temperature control with adding activators of some fungi such as </span><i><span style="font-family:Verdana;">Aspergillus sp</span></i><span style="font-family:Verdana;">, and </span><i><span style="font-family:Verdana;">Penicillium sp. </span></i><span style="font-family:Verdana;">The purpose of the research is to fill the research gap from previous studies of spent coffee grounds compost, which requires a long time in composting, so that if it is used directly on the soil and plants, the positive effect also requires a long time. The result of composting for 28 days with this method is that mature compost has black crumb and normal pH, with characteristics of C/N ratio below 10: C1 (7.06), C2 (6.99). This value is far from the control with a C/N ratio of 8.33. Decompose rate of macromolecule are above 40% for lignin and 70% for cellulose. Implementation of compost in radish plants, resulting Germination Index above 80% which indicates that the compost is ripe: control (92.39%), C1 (183.88%), C2 (191.86%). The results of the analysis with FTIR also showed that the compost was mature and stable, and rich in minerals. So, it can be concluded </span><span style="font-family:Verdana;">that</span><span style="font-family:Verdana;"> this composting method can speed up composting time and optimize the results of compost produced.</span>
文摘Using the shooting argument and an approximating method, this paper isconcerncd with the existence of fast-decay ground state of p-Laplacian equation: Apu＋f(u)=0, in Rn, where f(u) behaves just like f(u) = uq - us, as s>q>np/(n-p) - 1.
文摘In this paper, we discussed the influence of the initial tectonic stress on the relative measurement value of the ground stress when a long cylindrical straingauge is used in the viscoelastic media. We simulate the whole system consisting of the stratum, cement ring and the straingauge cylinder with a three layer medium model and obtain the solution of radial displacement on the inner wall of the straingauge under the action of initial tectonic stress by using the correspondence principle. The result showes: 1) The influence of initial stress making of the radial displacement on the inner wall of the straingauge increases gradually with time at a gradually reduced rate and tends to a certain value eventually; 2) The principal stress with a magnitude of [C 0+C 1 exp (- ω 1t)+ C 2 exp(- ω 2t )] σ i0 in the opposite direction of initial stress will be superimposed to the measuring result of stress change without considering the initial stress. where C 0, C 1, C 2 and ω 1, ω 2 are related only to the mechanical property of the stratum, σ i0 (i=1, 2) are the two principal components of the initial tectonic stress. It is pointed out that the initial tectonic stress affects obviously on the measurement of the relative change of ground stress in the cases of soft strata and high initial stress.
文摘The design procedure is made for a mine shaft where permanent underground facilities are interconnected. The highly faulted grounds were identified using empirical and semi-empirical theories. Furthermore, the behavior types are presented. This paper presents excavation and support methods in such ground conditions and the calculations results show that the installation of the yielding elements have an effect on support elements and prevent shotcrete damage during the curing stage. Different numerical analyses carried out showed that, with the yielding elements installed, the total displacements increase but the final axial force reduces, and therefore, the characteristic compressive strength of shotcrete is not exceeded. The calculation results of ground loads and displacements on the designed support system are presented with a 3D numerical geo-mechanical model adopted for highly faulted ground surrounding deeper complex underground structures.
基金supported by the National Natural Science Foundation of China(Grant Nos.42025601,92258303)the Scientific Research Fund of the Second Institute of Oceanography,MNR(Grant No.JB2501)。
文摘The Dangerous Grounds,located in the southern margin of the South China Sea,has experienced three distinct tectonic evolution stages during the Cenozoic:continental rifting,breakup from the South China Block and southward drift,and collision with Borneo,accompanied by a north-to-south shift in its paleogeographic environment.This study utilized a robust dataset comprising 67 seismic reflection profiles,integrated with drilling and dredging data,to reconstruct the sedimentary filling history of the Dangerous Grounds.By correlating sediment budget outcomes with the spatial distribution characteristics of the sediment thickness,we have gained valuable insights into the region's sedimentary evolution.Our findings reveal a progressive increase in sediment budgets across the three tectonic stages,despite relatively stable sediment budgets during the southward drift stage associated with seafloor spreading.Spatial sediment distribution shows a continued decrease in the east and expansion in the south and west.By integrating the temporal and spatial distribution of depocenters with drilling results and sediment provenance through geochemical analyses,we provide a comprehensive regional perspective on the factors controlling sediment budget trends,including regional tectonic events,monsoon,sea level change,and the river systems associated with paleogeographic environment variations.The sedimentary inputs to the Dangerous Grounds have shifted over time,with Paleocene-Eocene sediments primarily originating from the north.From the Oligocene to the Early Miocene,northern sediment supply progressively declined,while inputs from the southwest,transported through river systems originating in the Indochina and Malay Peninsulas,gradually increased.Since the Mid-Miocene,the collision with Borneo has led to enhanced sediment supply from the south,with sediments predominantly accumulating along slope edges,channel outlets,and within the Nansha Trough.
基金the National Key Research and Development Program(Grant No.2016YFB0100106)the Youth Innovation Promotion Association,Chinese Academy of Sciences(2015239)for financial supports.
文摘This paper reported the facile preparation of pyrolytic carbon derived from spent coffee grounds and the evaluation of its electrochemical performance when used as anode in sodium-ion battery.X-ray diffraction analysis,scanning electron microscope,Brunauer–Emmett–Teller were employed to characterize the structure of pyrolytic carbon.Electrochemical performances were tested by constant current charge–discharge,cyclic voltammetry and electrochemical impedance spectroscopy.Results showed that the pyrolytic carbon possess a porous structure(1–2 lm)and a specific surface area of 94.35 m2 g1.When used as anodes in sodium-ion batteries,a reversible capacity of 154.2 mA h g1 at a current density of 200 mA g1 after 50 cycles was obtained.Several electrolytes were evaluated and their electrochemical performances were compared.The result indicated that this material has excellent storage capacity and good cycling stability.Our method provided a preparation of pyrolytic carbon from environmentally friendly resources.
文摘Herein the biowaste by-product spent coffee grounds(SCGs)from coffee industry were incorporated into asphalt binders for performance enhancement.From the analysis of Fourier transform infrared spectroscopy(FTIR),differential scanning calorimetry(DSC),dynamic shear rheometer(DSR),and Brookfield viscosity rheometer,it is confirmed that SCGs have potential prospects as bio-waste modifiers in the application of sustainable pavements.Results demonstrated that the modification process was mainly based on physical reinforcement.Compared with that of the neat asphalt,the shearing stress-resistant ability and high-temperature performance of the SCGs modified binders with the appropriate addition presented a bit of improvement;whereas the binders with 1%and 3%SCGs exhibited remarkably enhanced low-temperature stability.However,notable weaknesses of practical performance were shown for the binder with excessive content of SCGs,indicating the necessity of proportion selecting before application.
文摘Outdoor tests are playing a more and more significant role in R & D of automobiles, especially prompt tests done in the proving ground which can extremely shorten the period of development. That is the reason that four proving ground have been set up in China. They are Hainan Proving Ground, Dongfeng Proving Ground, Dingyuan Proving Ground and Tongxian Proving Ground.
文摘Genetic screening has its uses:It helped A-list actor Angelina Jolie,for example,determine that she was at a high risk of breast cancer,leading to a preventative mastectomy.But what genetic screening can’t demonstrate is whether,broadly speaking,your child will have an aptitude for mathematics or sports.Certain specific health problems,yes;but sweeping statements about the future character of an adult?The scientific evidence for such tests was
文摘The main use for spent coffee grounds (SCG) produced in the soluble coffee industry is thermal energy generation in the industry itself. The SCG are processed using operations that are strongly dependent on powder flow behavior. In this study, we evaluated two classical flowability in dices of non-consolidated SCG powders: the angle of repose (AoR), and the Hausner ratio (HR). The influences of the mean particle diameter, particle size distribution (PSD), and water content on the AoR and HR values of SCG were analyzed for powders with a mean particle size range of 225-550 μm. For powders with a mean particle size close to 350 μm and for mixtures containing more than 40% fine particles, the HR (>1.35) and AoR (>45 °) values were characteristic of poor flowability. The AoR was sensitive to the powder PSD, and powders with similar mean particle sizes had higher AoR values when the PSD was larger. For powders w让h water contents up to 50%, the flowability indices were not greatly affected by the water content. A modified linear-mixture packing model was used to predict the packed bed void fractions for binary and ternary mixtures of the three base powders. The model was used to construct a ternary diagram to estimate the HR values of the mixtures. An equation was fitted to correlate HR and AoR. The proposed diagram and the equation provide insight into flow behavior and could be used for process design of industrial plants that handle SCG.
文摘EXCERPTS FROM MAJOR CHINESE MAGAZINES RETURN OF THE SAND MARTINS Oriental Outlook 29 May In late April,a sandy cliff along the Yongding River in southern Beijing became an unexpected attraction.Speckled with more than 100 nests built by sand martins,migratory birds that return to the city each summer,the site has become one of the largest breeding grounds for the species in the Chinese capital.Just a year ago,this fragile micro-habitat was nearly lost to a river management project.Fortunately,a group of bird-watchers spotted the threat in time and alerted city officials.
基金National Natural Science Foundation of China under Grant No.U2239252National Natural Science Foundation of China under Grant No.52279128Natural Science Foundation of Heilongjiang Province of China under Grant No.YQ2022E013。
文摘Dispatched by the Chinese government,a multidisciplinary team of 30 researchers collaborated with a team from Myanmar to conduct a 14-day on-site investigation.The work encompassed seismic intensity assessments,field surveys,and loss evaluations.The paper focuses on the intensity distribution and structural damage characteristics of the 2025 M7.9 Myanmar earthquake,yielding the following key findings.(1)The seismogenic fault rupture propagated in a nearly N-S direction,with a surface rupture length of approximately 450 km.The seismic impact zone exhibited an elongated N-S distribution and a shorter E-W span,distributed like a belt around the seismogenic fault.(2)Within the seismic impact zones,existing buildings comprised five primary structural types,with timber(bamboo)structures constituting the largest proportion(≈80%in rural areas,≈50%in urban areas).The relatively low disaster losses and casualties were primarily attributable to the good seismic performance and low damage ratio of timber(bamboo)structures across varying intensity zones.(3)An anomalous zone of intensityⅨwas located at the boundary between intensityⅥandⅦregions in Nay Pyi Taw.Here,ridge topography combined with soft soil layers significantly amplified ground motion,exacerbating structural damage.(4)Directional effects of ground motion were observed,with the structural damage phenomena and peak ground acceleration(PGA)values in the N-S direction exceeding those in the E-W direction.This validates that the maximum PGA distribution of strike-slip fault earthquakes aligns with the fault strike.The research is expected to provide technical support for post-disaster reconstruction planning,site selection,and disaster mitigation strategies in Myanmar.
