Biogenic coalbed gas,how it is generated and the geochemical characteristics of the gas are gaining global attention.The ways coalbed gas is generated,the status of research on the generation mechanism and the methods...Biogenic coalbed gas,how it is generated and the geochemical characteristics of the gas are gaining global attention.The ways coalbed gas is generated,the status of research on the generation mechanism and the methods of differentiating between biogenic gasses are discussed.The generation of biogenic coalbed methane is consistent with anaerobic fermentation theory.Commercial biogenic coalbed gas reservoirs are mainly generated by the process of CO2 reduction.The substrates used by the microbes living in the coal include organic compounds,CO2,H2 and acetate.The production ratio and quantity of biogenic coalbed methane depend on the exposed surface area,the solubility and permeability of the coal and the microbial concentration in the coal seam.It is generally believed that biogenic coalbed gas has a value for δ13C1<-5.5%,C1/C1+>0.95.The H isotope ratio is controlled by both the environment and the generation mechanism:typically δD1<-20%.Biogenic methane formed by CO2 reduction has more δD1 than that formed by acetate fermentation.展开更多
Organic matter(OM)is intimately associated with minerals in clay-rich mudstones,leading to widespread organic-mineral interaction during hydrocarbon generation in argillaceous source rocks.What we are concerned is the...Organic matter(OM)is intimately associated with minerals in clay-rich mudstones,leading to widespread organic-mineral interaction during hydrocarbon generation in argillaceous source rocks.What we are concerned is the effects of the different mineral properties on hydrocarbon generation process and mechanism during mineral transformation.In this way,pyrolysis experiments with smectite-octadecanoic acid complexes(Sm-OA and Ex-Sm-OA)were conducted to analyze correlation of mineralogy and pyrolysis behaviors.Based on organicmineral interaction,hydrocarbon generation process was divided into three phases.At 200–300℃,collapse of smectite led to desorption of OM,resulting in high yield of resin and slight increase in saturates.Subsequently,enhanced smectite illitization at 350–450℃was accompanied with large amounts of saturates and a mere gaseous hydrocarbon.Featured by neoformed plagioclase,ankerite,and illite,500C saw plenty of asphaltene and methane-rich gaseous hydrocarbons,revealing cracking reactions of OM.Noteworthy is that saturated and gaseous hydrocarbons in Ex-Sm-OA were considerably more than that in Sm-OA during second and third phases.Quantitative calculation of hydrogen revealed organic hydrogen provided by cross-linking of OM could not balance hydrogen consumed by cracking reactions,but supply of inorganic hydrogen ensured cracking could readily occur and consequently greatly promoted hydrocarbon generation.Further investigating characteristics of mineralogy and pyrolytic products,as well as effects of solid acidity on hydrocarbon generation,we concluded desorption of OM and decarboxylation promoted by Lewis acid were dominated at 200–300C,resulting in lowdegree hydrocarbon generation.While high yield of saturated and gaseous hydrocarbons in second and third phases,together with occurrence of ankerite,indicated predominance of decarboxylation and hydrogenation promoted by Lewis and Brønsted acid,respectively.Variations in organic-mineral interactions indicated(1)the controls of mineral transformation on hydrocarbon generation process and mechanism include desorption,decarboxylation,and hydrogenation reactions;(2)clay minerals acted as reactants evolving together with OM rather than catalysts.These findings are profoundly significant for understanding the hydrocarbon generation mechanisms,organic-inorganic interactions,and carbon cycle.展开更多
The current researches on the tooth surface mathematical equations and the theory of gearing mainly pay attention to the ordinary type worm gear set（e.g., ZN, ZA, or ZK）. The research of forming mechanism and three-...The current researches on the tooth surface mathematical equations and the theory of gearing mainly pay attention to the ordinary type worm gear set（e.g., ZN, ZA, or ZK）. The research of forming mechanism and three-dimensional modeling method for the double pitch worm gear set is not enough. So there are some difficulties in mathematical model deducing and geometry modeling of double pitch ZN-type worm gear set based on generation mechanism. In order to establish the mathematical model and the precise geometric model of double pitch ZN-type worm gear set, the structural characteristics and generation mechanism of the double pitch ZN-type worm gear set are investigated. Mathematical model of the ZN-type worm gear set is derived based on its generation mechanism and the theory of gearing. According to the mathematical model of the worm gear set which has been developed, a geometry modeling method of the double pitch ZN-type worm and worm gear is presented. Furthermore, a geometrical precision calculate method is proposed to evaluate the geometrical quality of the double pitch worm gear set. As a result, the maximum error is less than 6′10–4 mm in magnitude, thus the model of the double pitch ZN-type worm gear set is available to meet the requirements of finite element analysis and engineering application. The derived mathematical model and the proposed geometrical modeling method are helpful to guiding the design, manufacture and contact analysis of the worm gear set.展开更多
Effectively identifying and preventing the threat of Byzantine nodes to the security of distributed systems is a challenge in applying consortium chains.Therefore,this paper proposes a new consortium chain generation ...Effectively identifying and preventing the threat of Byzantine nodes to the security of distributed systems is a challenge in applying consortium chains.Therefore,this paper proposes a new consortium chain generation model,deeply analyzes the vulnerability of the consortium chain consensus based on the behavior of the nodes,and points out the effects of Byzantine node proportion and node state verification on the consensus process and system security.Furthermore,the normalized verification node aggregation index that represents the consensus ability of the consortium organization and the trust evaluation function of the verification node set is derived.When either of the two is lower than the threshold,the consortium institution or the verification node set members are dynamically adjusted.On this basis,an innovative consortium chain generation mechanism based on the Asynchronous Binary Byzantine Consensus Mechanism(ABBCM)is proposed.Based on the extended consortium chain consensus mechanism,a certain consensus value set can be combined into multiple proposals,which can realize crossdomain asynchronous message passing between multi-consortium chains without reducing the system’s security.In addition,experiments are carried out under four classical Byzantine Attack(BA)behaviors,BA1 to BA4.The results show that the proposed method can obtain better delay than the classical random Byzantine consensus algorithm Coin,effectively improving the consensus efficiency based on asynchronous message passing in the consortium chain and thus meeting the throughput of most Internet of Things(IoT)applications.展开更多
The exposed surface of the dry salt lake basin contains a large number of extremely fine lightweight saline-alkali(mixed)dust and clay dust.It is extremely easy to dust and since saline-alkali lake is low-lying and it...The exposed surface of the dry salt lake basin contains a large number of extremely fine lightweight saline-alkali(mixed)dust and clay dust.It is extremely easy to dust and since saline-alkali lake is low-lying and its temperature展开更多
The overproduction of free radicals is the main reason for the peroxidation damage, metabolic disturbance and antioxidant imbalance in animals. This paper summarized the types and generation mechanism of intracellular...The overproduction of free radicals is the main reason for the peroxidation damage, metabolic disturbance and antioxidant imbalance in animals. This paper summarized the types and generation mechanism of intracellular free radicals and clarified the sources of free radicals in skeletal muscles and digestive tracts of animals.展开更多
The extra heat generation in spin transport is usually interpreted in terms of the spin relaxation. Reformulating the heat generation rate, we find alternative current-force pairs without cross effects, which enable u...The extra heat generation in spin transport is usually interpreted in terms of the spin relaxation. Reformulating the heat generation rate, we find alternative current-force pairs without cross effects, which enable us to interpret the product of each pair as a distinct mechanism of heat generation. The results show that the spin-dependent part of the heat generation includes two terms. One is proportional to the square of the spin accumulation and arises from the spin relaxation. However, the other is proportional to the square of the spin-accumulation gradient and should be attributed to another mechanism, the spin diffusion. We illustrate the characteristics of the two mechanisms in a typical spin valve with a finite nonmagnetic spacer layer.展开更多
The tourist’s sense of place plays a pivotal role in the protection and renovation of historical districts,and it is an important driving force for the development,evolution and spatial reconstruction of historic dis...The tourist’s sense of place plays a pivotal role in the protection and renovation of historical districts,and it is an important driving force for the development,evolution and spatial reconstruction of historic districts.This study examines the cognitive,emotional,and behavioral characteristics of tourists through the framework of sense of place(SoP),using Yongqingfang—a representative historical district in Guangdong—as a case study.Additionally,it proposes a model to elucidate the mechanisms underlying the generation of sense of place.The findings indicate that perception of place activities and the perception of place environment positively influence tourists’positive emotional responses and their behavioral intentions.Based on the analysis of the results of hypothesis testing,the study also tested the mediating effects of positive and negative place emotions.It was determined that tourists generate place emotions in their cognition and experience of a place,and these emotions subsequently influence their behavior intentions.The study provides theoretical guidance for the choice of development pathways,renovation and reconstruction of historical districts from the perspective of the generation mechanism of tourists’sense of place.展开更多
In this study, we use the Bohai Sea area as an example to investigate the characteristics of secondary microseisms and their impact on seismic noise based on the temporal frequency spectral analysis of observation dat...In this study, we use the Bohai Sea area as an example to investigate the characteristics of secondary microseisms and their impact on seismic noise based on the temporal frequency spectral analysis of observation data from 33 broadband seismic stations during strong gust periods, and new perspectives are proposed on the generation mechanisms of secondary microseisms. The results show that short-period double- frequency (SPDF) and long-period double-frequency (LPDF) microseisms exhibit significant alternating trends of strengthening and weakening in the northwest area of the Bohai Sea. SPDF microseisms are generated by irregular wind waves during strong off shore wind periods, with a broad frequency band distributed in the range of 0.2-1 Hz;LPDF microseisms are generated by regular swells during periods of sea wind weakening, with a narrow frequency band concentrated between 0.15 and 0.3 Hz. In terms of temporal dimensions, as the sea wind weakens, the energy of SPDF microseisms weakens, and the dominant frequencies increase, whereas the energy of LPDF microseisms strengthens and the dominant frequencies decrease, which is consistent with the process of the decay of wind waves and the growth of swells. In terms of spatial dimensions, as the microseisms propagate inland areas, the advantageous frequency band and energy of SPDF microseisms are reduced and significantly attenuated, respectively, whereas LPDF microseisms show no significant changes. And during the propagation process in high-elevation areas, LPDF microseisms exhibit a certain site amplifi cation eff ect when the energy is strong. The results provide important supplements to the basic theory of secondary microseisms, preliminarily reveal the relationship between the atmosphere, ocean, and seismic noise, and provide important theoretical references for conducting geological and oceanographic research based on the characteristics of secondary microseisms.展开更多
Some crustal-deformation data related to the Ms8.0 Wenchuan in 2008, was described and a model that is capable of explaining the observed deformation features is presented. The data include ： pre-earthquake uplift in...Some crustal-deformation data related to the Ms8.0 Wenchuan in 2008, was described and a model that is capable of explaining the observed deformation features is presented. The data include ： pre-earthquake uplift in an area south of the epicenter obtained by repeated-leveling measurements ; pre-earthquake horizontal deformation by GPS observation during two periods in Sichuan-Yunnan area;vertical deformation along a short cross-fault leveling line in the epicenter area; and co-seismic near-field vertical and horizontal crustal-move- ment data by GPS. The model is basically ＂elastic-rebound＂, but involves a zone between two local faults that was squeezed out at the time of earthquake. ：展开更多
It is well known that energy-momentum is the source of gravitational field. For a long time, it is generally believed that only stars with huge masses can generate strong gravitational field. Based on the unified theo...It is well known that energy-momentum is the source of gravitational field. For a long time, it is generally believed that only stars with huge masses can generate strong gravitational field. Based on the unified theory of gravitational interactions and electromagnetic interactions, a new mechanism of the generation of gravitational field is studied. According to this mechanism, in some special conditions, electromagnetic energy can be directly converted into gravitational energy, and strong gravitational field can be generated without massive stars. Gravity impulse found in experiments is generated by this mechanism.展开更多
A preliminary field-based investigation was undertaken in a small(<10 km^(2))river valley located in the mountainous Jura region of northwest Switzerland.The aims of the work were to assess sediment generation and ...A preliminary field-based investigation was undertaken in a small(<10 km^(2))river valley located in the mountainous Jura region of northwest Switzerland.The aims of the work were to assess sediment generation and annual sediment transport rates by tree throw on forested hillslopes,and to document surface hydrology characteristics on four fresh soil mounds associated with recent tree throws over a 24-day monitoring period.For the soil mounds,average sediment recovery ranged from 7.7-28.2 g(dry weight),equivalent to a suspended sediment concentration of 145.2-327.8 g L^(-1),and runoff coefficients ranged from 1.0%-4.2%.Based on a soil bulk density value of 1,044 kg m^(-3),upslope runoff generation areas were denuded by an average 0.14 mm by the end of the 24-day monitoring period,representing an erosion rate equivalent to 2.1 mm yr^(-1).A ca.50 cm high soil mound could therefore feasibly persist for around 200-250 years.For tree throw work,the dimensions of 215 individual tree throws were measured and their locations mapped in 12 separate locations along the river valley representing a cumulative area equivalent to 5.3 ha(av.density,43 per ha).Tree throws generated a total of 20.1 m^(3) of fine-sediment(<2 mm diameter),or the equivalent of 3.8×10^(-4) m^(3) m^(-2).The process of tree throw was originally attributed to two extreme weather events that occurred in west and central Europe in late December 1999.Taking the 18-year period since both storms,this represents an annual sediment transport rate of 2.7×10^(-5) m^(3) m^(-1) yr^(-1).Exploring the relationship with wind on fall direction,65.5%of tree throws(143)generally fell in a downslope direction irrespective of hillslope aspect on which they were located.This infers that individual storms may not have been responsible for the majority of tree throws,but instead,could be associated with root failure.Given the high density of tree throws and their relative maturity(average age 41 years),we hypothesise that once trees attain a certain age in this river valley,their physiognomy(i.e.height,mass and centre of gravity)compromises their ability to remain securely anchored.We tentatively attribute this possibility to the presence of bedrock close to the surface,and to the shallow soil profile overlaying steep hillslopes.展开更多
Source and occurrence of Excess Coalbed Methane is a long-term concern research topic in Coal Geology and Structural Geology. Since it is essential to understand the outburst mechanism of coal gas, and to support the ...Source and occurrence of Excess Coalbed Methane is a long-term concern research topic in Coal Geology and Structural Geology. Since it is essential to understand the outburst mechanism of coal gas, and to support the coalbed methane development projects as the theoretical basis. We found in the study that, huge imparity is behind the evolutionary trend on molecular structure and the mechanism of influence from different deformation. The thesis demonstrates its probable routes of gas evolution according to distinct deformation mechanisms of coal. In the role of brittle deformation mechanism, a rapidly formed advantage rupture surface along with sliding motion from which has worked on coal. As another result, mechanical energy has transformed into friction and kinetic energy during the process. Kinetic energy increases simultaneously, which brings some results, that the new generated gas molecule. While the chemical structure of coal remains in a steady-state and do not react easily an outburst with gas. Mechanical energy turns into strain energy through its ductile deformation mechanism. The dislocation or lamellar slip made disordered between the constitutional units of aromatic rings and aromatic lamellas, as soon as secondary structural defects created. On another hand, molecular motion accelerates and splits off the small molecular on the side chain, due to the dissociation of aromatic nucleus;CH<sub>4 </sub>gas molecular was generated and placed in the secondary structural defect of coal, along with a great deal of strain energy in non-steady-state. By breaking away the balance maintaining terms, huge strain energy releases suddenly, small moleculars are free from the secondary structure defect, react outburst with gas. Furthermore to extend the discussion of the conventional physical ideas on coal absorb gas, according to the phenomenon of exceeded CBM, the gas molecular has a significant chance existing in a low bond energy of chemical bonds of coal structure.展开更多
Enterprises engaging in collaboration with competitors can increase their technological diversity and release a new product innovation, but also full of challenges. This complexity of co-opetition relationship require...Enterprises engaging in collaboration with competitors can increase their technological diversity and release a new product innovation, but also full of challenges. This complexity of co-opetition relationship requirements academia and enterprises to clarify the problem of competitive technology alliance risk formation mechanism, making the risk control to dispose. Based on the perspective of resources and capabilities, this paper firstly puts forward the double helix model of alliances＇ evolution on resources and capabilities ; then, with the deepe- ning of the cooperation, this evolutionary process leads to different innovation risk： opportunism, R and D inte- gration risk and flexible loss risk; next, analyzing the corresponding management path and constructing the conceptual framework of risk management mechanism to help enterprise using the co-opetition relationship to reduce risk and improve the potential competitive advantage.展开更多
With the increasing attention paid to battery technology,the microscopic reaction mechanism and macroscopic heat transfer process of lithium-ion batteries have been further studied and understood from both academic an...With the increasing attention paid to battery technology,the microscopic reaction mechanism and macroscopic heat transfer process of lithium-ion batteries have been further studied and understood from both academic and industrial perspectives.Temperature,as one of the key parameters in the physical fra mework of batteries,affects the performa nce of the multi-physical fields within the battery,a nd its effective control is crucial.Since the heat generation in the battery is determined by the real-time operating conditions,the battery temperature is essentially controlled by the real-time heat dissipation conditions provided by the battery thermal management system.Conventional battery thermal management systems have basic temperature control capabilities for most conventional application scenarios.However,with the current development of la rge-scale,integrated,and intelligent battery technology,the adva ncement of battery thermal management technology will pay more attention to the effective control of battery temperature under sophisticated situations,such as high power and widely varied operating conditions.In this context,this paper presents the latest advances and representative research related to battery thermal management system.Firstly,starting from battery thermal profile,the mechanism of battery heat generation is discussed in detail.Secondly,the static characteristics of the traditional battery thermal management system are summarized.Then,considering the dynamic requirements of battery heat dissipation under complex operating conditions,the concept of adaptive battery thermal management system is proposed based on specific research cases.Finally,the main challenges for battery thermal management system in practice are identified,and potential future developments to overcome these challenges are presented and discussed.展开更多
The south-western Ordos Basin is rich in low-middle rank coalbed methane(CBM)resources;while the geochemical characteristics and genetic mechanism of CBM are not clear.Herein,according to geological and geochemical te...The south-western Ordos Basin is rich in low-middle rank coalbed methane(CBM)resources;while the geochemical characteristics and genetic mechanism of CBM are not clear.Herein,according to geological and geochemical test data from gas and coal seam water from CBM wells in Bingchang,Jiaoxun,Huangling,Yonglong,and Longdong minging areas,we systematically studied the geochemical characteristics,generation,and evolution mechanism of CBM in Jurassic Yan’an Formation in the south-western Ordos Basin.The results show that the CH4 content of whole gas is in the range of 42.01%-94.72%.The distribution ranges of theδ^(13)C-CH_(4)value is−87.2‰to−32.5‰,indicating diverse sources of thermogenic gas and biogenic gas.The microbial methane is mainly generated by a CO_(2)reduction pathway,with certain methyl-type fermentation spots.Theδ^(13)C-CH_(4)has a positive correlation with burial depth,indicating the obvious fractionation of CBM.The relationship between the genetic types and burial depth of the CBM reservoir indicates that the favorable depth of secondary biogenic gas is less than 660 m.The Late Cretaceous Yanshanian Movement led to the uplift of the Ordos Basin,and a large amount of thermogenic gas escaped from the edge of the basin.Since the Paleogene Period,the coal reservoir in the basin margin has received recharge from atmospheric precipitation,which is favorable for the formation of secondary biogenic methane.The deep area,generally under 1000 m,mainly contains residual thermogenic gas.The intermediate transition zone is mixed gas.Constrained by the tectonic background,the genetic types of CBM in different mining areas are controlled by the coupling of burial depth,coal rank,and hydrogeological conditions.The Binchang mining area contains biogenic gas,and the development of CBM has achieved initial success,indicating that similar blocks with biogenic gas formation conditions is key to the efficient development of CBM.The research results provide a scientific basis for searching for favorable exploration areas of CBM in the south-western Ordos Basin.展开更多
As a potential renewable and clean energy source,the distribution and exploration prospects of natural hydrogen have garnered widespread attention.However,the limitations in understanding the formation mechanisms and ...As a potential renewable and clean energy source,the distribution and exploration prospects of natural hydrogen have garnered widespread attention.However,the limitations in understanding the formation mechanisms and accumulation patterns of underground natural hydrogen have significantly constrained its efficient exploration and utilization.This study reports H_(2)content and isotopes in natural gas from deep formations in sedimentary basins through geochemical analysis of 58 conventional gas samples from the Sinian to Triassic strata in the central Sichuan Basin.We discovered that H_(2)content in deep natural gas in central Sichuan generally exceeds 0.1%,with a maximum of 1.6%,and hydrogen isotopes(δ^(2)H_(H_(2)))range from-850‰to-586‰.Analysis of the geological conditions,hydrogen generation mechanisms,and isotope fractionation characteristics in the study area confirms that microbial fermentation or in-situ organic matter cracking are not effective pathways for deep H_(2)generation.Combined with helium content and isotope analysis of the natural gas,it is inferred that the volcanic basement in the central Sichuan area is the potential source rock for natural H_(2)in the Sinian to Triassic strata.Specifically,H_(2)originates from the radiolysis of water and hydrothermal reactions of Fe(Ⅱ)in the basement granite.Additionally,a diffusion fractionation model reveals significant isotope fractionation during the migration and accumulation of deep H_(2)into sedimentary reservoirs,which lead to anomalously light δ^(2)H_(H_(2))in deep natural gas in central Sichuan.This indicates that the underground natural hydrogen accumulation is in a long-term dynamic process,with simultaneous H_(2)accumulation and dissipation in the gas reservoirs.This research not only elucidates the formation mechanism of deep H_(2)but also provides insights for the resource potential of natural hydrogen in sedimentary basins.展开更多
In recent years,tuned liquid dampers(TLDs)have attracted significant research interest;however,overall progress has been limited due to insufficient understanding of the mechanisms governing sloshing-induced loads.In ...In recent years,tuned liquid dampers(TLDs)have attracted significant research interest;however,overall progress has been limited due to insufficient understanding of the mechanisms governing sloshing-induced loads.In particular,it remains unclear whether the water in aqueducts—common water-diversion structures in many countries—can serve as an effective TLD.This study investigates the generation mechanisms of sloshing loads during the first-order transverse resonance of water in a U-shaped aqueduct using a two-dimensional(2D)numerical model.The results reveal that,at the equilibrium position,the free surface difference between the left and right walls,the horizontal force on the aqueduct,and the fluctuating component of the vertical force all reach their maxima,with energy predominantly stored as potential energy.At the maximum displacement position,the surface difference and horizontal force drop to zero,while the fluctuating vertical force attains its minimum and energy shifts primarily to kinetic form.At this stage,static pressure is governed solely by the vertical convective acceleration,whereas at equilibrium it is closely linked to both the free surface difference and vertical local acceleration of the water.This dynamic energy exchange generates vertical force oscillations even when the free surface appears nearly symmetric.展开更多
The filter capacitor stack is one of the main acoustic noise sources in high-voltage DC(HVDC) converter stations.As HVDC systems are built more and more recently,it is significant to research the audible noise of filt...The filter capacitor stack is one of the main acoustic noise sources in high-voltage DC(HVDC) converter stations.As HVDC systems are built more and more recently,it is significant to research the audible noise of filter capacitors.In this paper,the current situation of research on vibration and audible noise of filter capacitors in HVDC converter stations,which is departed into three parts—generation mechanism,prediction methods,and reduction measures,is presented and the research achievements are discussed.Scholars have built the model that the alternating electric force caused by the voltage conduces to the vibration,which propagates to the enclosure and radiates audible noise.As a result,the parts contributing most to the generation of audible noise are the top and the bottom of capacitors. In the noise level prediction respect,several methods have been prospected including impact hammer,sweep frequency, impact current,monopole and Kirchhoff formula method,which are suitable for single capacitors or capacitors stacks individually.However,the sweep frequency method is restricted by experiment condition,and the impact current method needs further research and verified.On the other hand,CIGRE WG14.26 provides three sound reduction measures,but all of them are not so practicable,while MPP absorber and compressible space absorber prospected by Dr.Wu Peng are proved to be effective.The sound barriers are also considered by scholars,and the acoustic directivity performance of capacitors is also researched.Besides,the developing direction of each research field is prospected in corresponding part.展开更多
Tailored surface textures at the micro- or nanoscale dimensions are widely used to get required functional performances. Rotary ultrasonic texturing （RUT） technique has been proved to be capable of fabricating perio...Tailored surface textures at the micro- or nanoscale dimensions are widely used to get required functional performances. Rotary ultrasonic texturing （RUT） technique has been proved to be capable of fabricating periodic micro- and nanostructures. In the present study, diamond tools with geometrically defined cutting edges were designed for fabricating different types of tailored surface textures using the RUT method. Surface generation mechanisms and machinable structures of the RUT process are analyzed and simulated with a 3D-CAD program. Textured surfaces generated by using a triangular pyramid cutting tip are constructed. Different textural patterns from several micrometers to several tens of micrometers with few burrs were successfully fabricated, which proved that tools with a proper two-rake-face design are capable of removing cutting chips efficiently along a sinusoidal cutting locus in the RUT process. Technical applications of the textured surfaces are also discussed. Wetting properties of textured aluminum surfaces were evaluated by combining the test of surface roughness features. The results show that the real surface area of the textured aluminum surfaces almost doubled by comparing with that of a flat surface, and anisotropic wetting properties were obtained due to the obvious directional textural features.展开更多
基金provided by the National Natural Science Foundation of China (No.40730422) is gratefully acknowledged
文摘Biogenic coalbed gas,how it is generated and the geochemical characteristics of the gas are gaining global attention.The ways coalbed gas is generated,the status of research on the generation mechanism and the methods of differentiating between biogenic gasses are discussed.The generation of biogenic coalbed methane is consistent with anaerobic fermentation theory.Commercial biogenic coalbed gas reservoirs are mainly generated by the process of CO2 reduction.The substrates used by the microbes living in the coal include organic compounds,CO2,H2 and acetate.The production ratio and quantity of biogenic coalbed methane depend on the exposed surface area,the solubility and permeability of the coal and the microbial concentration in the coal seam.It is generally believed that biogenic coalbed gas has a value for δ13C1<-5.5%,C1/C1+>0.95.The H isotope ratio is controlled by both the environment and the generation mechanism:typically δD1<-20%.Biogenic methane formed by CO2 reduction has more δD1 than that formed by acetate fermentation.
基金the National Natural Science Foundation of China(Grant Nos.41672115 and 41972126)the National Oil and Gas Special Fund(Grant No.2016ZX05006001-003).
文摘Organic matter(OM)is intimately associated with minerals in clay-rich mudstones,leading to widespread organic-mineral interaction during hydrocarbon generation in argillaceous source rocks.What we are concerned is the effects of the different mineral properties on hydrocarbon generation process and mechanism during mineral transformation.In this way,pyrolysis experiments with smectite-octadecanoic acid complexes(Sm-OA and Ex-Sm-OA)were conducted to analyze correlation of mineralogy and pyrolysis behaviors.Based on organicmineral interaction,hydrocarbon generation process was divided into three phases.At 200–300℃,collapse of smectite led to desorption of OM,resulting in high yield of resin and slight increase in saturates.Subsequently,enhanced smectite illitization at 350–450℃was accompanied with large amounts of saturates and a mere gaseous hydrocarbon.Featured by neoformed plagioclase,ankerite,and illite,500C saw plenty of asphaltene and methane-rich gaseous hydrocarbons,revealing cracking reactions of OM.Noteworthy is that saturated and gaseous hydrocarbons in Ex-Sm-OA were considerably more than that in Sm-OA during second and third phases.Quantitative calculation of hydrogen revealed organic hydrogen provided by cross-linking of OM could not balance hydrogen consumed by cracking reactions,but supply of inorganic hydrogen ensured cracking could readily occur and consequently greatly promoted hydrocarbon generation.Further investigating characteristics of mineralogy and pyrolytic products,as well as effects of solid acidity on hydrocarbon generation,we concluded desorption of OM and decarboxylation promoted by Lewis acid were dominated at 200–300C,resulting in lowdegree hydrocarbon generation.While high yield of saturated and gaseous hydrocarbons in second and third phases,together with occurrence of ankerite,indicated predominance of decarboxylation and hydrogenation promoted by Lewis and Brønsted acid,respectively.Variations in organic-mineral interactions indicated(1)the controls of mineral transformation on hydrocarbon generation process and mechanism include desorption,decarboxylation,and hydrogenation reactions;(2)clay minerals acted as reactants evolving together with OM rather than catalysts.These findings are profoundly significant for understanding the hydrocarbon generation mechanisms,organic-inorganic interactions,and carbon cycle.
基金Supported by Major National Basic Research Program of China(973Program,Grant No.2011CB013400-05)PhD Programs Foundation of Ministry of Education of China(Grant No.20110191110005)
文摘The current researches on the tooth surface mathematical equations and the theory of gearing mainly pay attention to the ordinary type worm gear set（e.g., ZN, ZA, or ZK）. The research of forming mechanism and three-dimensional modeling method for the double pitch worm gear set is not enough. So there are some difficulties in mathematical model deducing and geometry modeling of double pitch ZN-type worm gear set based on generation mechanism. In order to establish the mathematical model and the precise geometric model of double pitch ZN-type worm gear set, the structural characteristics and generation mechanism of the double pitch ZN-type worm gear set are investigated. Mathematical model of the ZN-type worm gear set is derived based on its generation mechanism and the theory of gearing. According to the mathematical model of the worm gear set which has been developed, a geometry modeling method of the double pitch ZN-type worm and worm gear is presented. Furthermore, a geometrical precision calculate method is proposed to evaluate the geometrical quality of the double pitch worm gear set. As a result, the maximum error is less than 6′10–4 mm in magnitude, thus the model of the double pitch ZN-type worm gear set is available to meet the requirements of finite element analysis and engineering application. The derived mathematical model and the proposed geometrical modeling method are helpful to guiding the design, manufacture and contact analysis of the worm gear set.
基金supported by Henan University Science and Technology Innovation Talent Support Program(23HASTIT029)the National Natural Science Foundation of China(61902447)+3 种基金Tianjin Natural Science Foundation Key Project(22JCZDJC00600)Research Project of Humanities and Social Sciences in Universities of Henan Province(2024-ZDJH-061)Key Scientific Research Projects of Colleges and Universities in Henan Province(23A520054)Henan Science and Technology Research Project(232102210124).
文摘Effectively identifying and preventing the threat of Byzantine nodes to the security of distributed systems is a challenge in applying consortium chains.Therefore,this paper proposes a new consortium chain generation model,deeply analyzes the vulnerability of the consortium chain consensus based on the behavior of the nodes,and points out the effects of Byzantine node proportion and node state verification on the consensus process and system security.Furthermore,the normalized verification node aggregation index that represents the consensus ability of the consortium organization and the trust evaluation function of the verification node set is derived.When either of the two is lower than the threshold,the consortium institution or the verification node set members are dynamically adjusted.On this basis,an innovative consortium chain generation mechanism based on the Asynchronous Binary Byzantine Consensus Mechanism(ABBCM)is proposed.Based on the extended consortium chain consensus mechanism,a certain consensus value set can be combined into multiple proposals,which can realize crossdomain asynchronous message passing between multi-consortium chains without reducing the system’s security.In addition,experiments are carried out under four classical Byzantine Attack(BA)behaviors,BA1 to BA4.The results show that the proposed method can obtain better delay than the classical random Byzantine consensus algorithm Coin,effectively improving the consensus efficiency based on asynchronous message passing in the consortium chain and thus meeting the throughput of most Internet of Things(IoT)applications.
文摘The exposed surface of the dry salt lake basin contains a large number of extremely fine lightweight saline-alkali(mixed)dust and clay dust.It is extremely easy to dust and since saline-alkali lake is low-lying and its temperature
基金Supported by Natural Science Foundation of Hubei Province(2013CFA100)National Natural Science Foundation of China(31472117)
文摘The overproduction of free radicals is the main reason for the peroxidation damage, metabolic disturbance and antioxidant imbalance in animals. This paper summarized the types and generation mechanism of intracellular free radicals and clarified the sources of free radicals in skeletal muscles and digestive tracts of animals.
基金Supported by the National Natural Science Foundation of China under Grant Nos 11404013,11605003,61405003,11174020 and 11474012the Scientific Research Project of Beijing Educational Committee under Grant No KM201510011002the 2016 Graduate Research Program of Beijing Technology and Business University
文摘The extra heat generation in spin transport is usually interpreted in terms of the spin relaxation. Reformulating the heat generation rate, we find alternative current-force pairs without cross effects, which enable us to interpret the product of each pair as a distinct mechanism of heat generation. The results show that the spin-dependent part of the heat generation includes two terms. One is proportional to the square of the spin accumulation and arises from the spin relaxation. However, the other is proportional to the square of the spin-accumulation gradient and should be attributed to another mechanism, the spin diffusion. We illustrate the characteristics of the two mechanisms in a typical spin valve with a finite nonmagnetic spacer layer.
基金The Key Program of National Social Science Funds of China(23AZD062)。
文摘The tourist’s sense of place plays a pivotal role in the protection and renovation of historical districts,and it is an important driving force for the development,evolution and spatial reconstruction of historic districts.This study examines the cognitive,emotional,and behavioral characteristics of tourists through the framework of sense of place(SoP),using Yongqingfang—a representative historical district in Guangdong—as a case study.Additionally,it proposes a model to elucidate the mechanisms underlying the generation of sense of place.The findings indicate that perception of place activities and the perception of place environment positively influence tourists’positive emotional responses and their behavioral intentions.Based on the analysis of the results of hypothesis testing,the study also tested the mediating effects of positive and negative place emotions.It was determined that tourists generate place emotions in their cognition and experience of a place,and these emotions subsequently influence their behavior intentions.The study provides theoretical guidance for the choice of development pathways,renovation and reconstruction of historical districts from the perspective of the generation mechanism of tourists’sense of place.
基金supported by Earthquake Science and Technology Spark Program of China Earthquake Administration (No. XH20006Y)Local Standards Formulation and Revision Program of Hebei Province (No. FW202154)+1 种基金Earthquake Science and Technology Spark Program of Hebei Earthquake Agency (No. DZ2024112100002)2023 Seismological Data Sharing Project of China Earthquake Networks Center (Dataset Project)。
文摘In this study, we use the Bohai Sea area as an example to investigate the characteristics of secondary microseisms and their impact on seismic noise based on the temporal frequency spectral analysis of observation data from 33 broadband seismic stations during strong gust periods, and new perspectives are proposed on the generation mechanisms of secondary microseisms. The results show that short-period double- frequency (SPDF) and long-period double-frequency (LPDF) microseisms exhibit significant alternating trends of strengthening and weakening in the northwest area of the Bohai Sea. SPDF microseisms are generated by irregular wind waves during strong off shore wind periods, with a broad frequency band distributed in the range of 0.2-1 Hz;LPDF microseisms are generated by regular swells during periods of sea wind weakening, with a narrow frequency band concentrated between 0.15 and 0.3 Hz. In terms of temporal dimensions, as the sea wind weakens, the energy of SPDF microseisms weakens, and the dominant frequencies increase, whereas the energy of LPDF microseisms strengthens and the dominant frequencies decrease, which is consistent with the process of the decay of wind waves and the growth of swells. In terms of spatial dimensions, as the microseisms propagate inland areas, the advantageous frequency band and energy of SPDF microseisms are reduced and significantly attenuated, respectively, whereas LPDF microseisms show no significant changes. And during the propagation process in high-elevation areas, LPDF microseisms exhibit a certain site amplifi cation eff ect when the energy is strong. The results provide important supplements to the basic theory of secondary microseisms, preliminarily reveal the relationship between the atmosphere, ocean, and seismic noise, and provide important theoretical references for conducting geological and oceanographic research based on the characteristics of secondary microseisms.
基金supported by the north-east margin area of Qinghai-Tibetplateau,from the research project of integrated observation of geophysicsfields for China(200908029-5)Tianjin research project on basic appli-cation and front technology(08JCZDJC18900)
文摘Some crustal-deformation data related to the Ms8.0 Wenchuan in 2008, was described and a model that is capable of explaining the observed deformation features is presented. The data include ： pre-earthquake uplift in an area south of the epicenter obtained by repeated-leveling measurements ; pre-earthquake horizontal deformation by GPS observation during two periods in Sichuan-Yunnan area;vertical deformation along a short cross-fault leveling line in the epicenter area; and co-seismic near-field vertical and horizontal crustal-move- ment data by GPS. The model is basically ＂elastic-rebound＂, but involves a zone between two local faults that was squeezed out at the time of earthquake. ：
文摘It is well known that energy-momentum is the source of gravitational field. For a long time, it is generally believed that only stars with huge masses can generate strong gravitational field. Based on the unified theory of gravitational interactions and electromagnetic interactions, a new mechanism of the generation of gravitational field is studied. According to this mechanism, in some special conditions, electromagnetic energy can be directly converted into gravitational energy, and strong gravitational field can be generated without massive stars. Gravity impulse found in experiments is generated by this mechanism.
基金funded by the Physical Geography and Environmental Change Research Group,Department of Environmental Sciences,University of Basel。
文摘A preliminary field-based investigation was undertaken in a small(<10 km^(2))river valley located in the mountainous Jura region of northwest Switzerland.The aims of the work were to assess sediment generation and annual sediment transport rates by tree throw on forested hillslopes,and to document surface hydrology characteristics on four fresh soil mounds associated with recent tree throws over a 24-day monitoring period.For the soil mounds,average sediment recovery ranged from 7.7-28.2 g(dry weight),equivalent to a suspended sediment concentration of 145.2-327.8 g L^(-1),and runoff coefficients ranged from 1.0%-4.2%.Based on a soil bulk density value of 1,044 kg m^(-3),upslope runoff generation areas were denuded by an average 0.14 mm by the end of the 24-day monitoring period,representing an erosion rate equivalent to 2.1 mm yr^(-1).A ca.50 cm high soil mound could therefore feasibly persist for around 200-250 years.For tree throw work,the dimensions of 215 individual tree throws were measured and their locations mapped in 12 separate locations along the river valley representing a cumulative area equivalent to 5.3 ha(av.density,43 per ha).Tree throws generated a total of 20.1 m^(3) of fine-sediment(<2 mm diameter),or the equivalent of 3.8×10^(-4) m^(3) m^(-2).The process of tree throw was originally attributed to two extreme weather events that occurred in west and central Europe in late December 1999.Taking the 18-year period since both storms,this represents an annual sediment transport rate of 2.7×10^(-5) m^(3) m^(-1) yr^(-1).Exploring the relationship with wind on fall direction,65.5%of tree throws(143)generally fell in a downslope direction irrespective of hillslope aspect on which they were located.This infers that individual storms may not have been responsible for the majority of tree throws,but instead,could be associated with root failure.Given the high density of tree throws and their relative maturity(average age 41 years),we hypothesise that once trees attain a certain age in this river valley,their physiognomy(i.e.height,mass and centre of gravity)compromises their ability to remain securely anchored.We tentatively attribute this possibility to the presence of bedrock close to the surface,and to the shallow soil profile overlaying steep hillslopes.
文摘Source and occurrence of Excess Coalbed Methane is a long-term concern research topic in Coal Geology and Structural Geology. Since it is essential to understand the outburst mechanism of coal gas, and to support the coalbed methane development projects as the theoretical basis. We found in the study that, huge imparity is behind the evolutionary trend on molecular structure and the mechanism of influence from different deformation. The thesis demonstrates its probable routes of gas evolution according to distinct deformation mechanisms of coal. In the role of brittle deformation mechanism, a rapidly formed advantage rupture surface along with sliding motion from which has worked on coal. As another result, mechanical energy has transformed into friction and kinetic energy during the process. Kinetic energy increases simultaneously, which brings some results, that the new generated gas molecule. While the chemical structure of coal remains in a steady-state and do not react easily an outburst with gas. Mechanical energy turns into strain energy through its ductile deformation mechanism. The dislocation or lamellar slip made disordered between the constitutional units of aromatic rings and aromatic lamellas, as soon as secondary structural defects created. On another hand, molecular motion accelerates and splits off the small molecular on the side chain, due to the dissociation of aromatic nucleus;CH<sub>4 </sub>gas molecular was generated and placed in the secondary structural defect of coal, along with a great deal of strain energy in non-steady-state. By breaking away the balance maintaining terms, huge strain energy releases suddenly, small moleculars are free from the secondary structure defect, react outburst with gas. Furthermore to extend the discussion of the conventional physical ideas on coal absorb gas, according to the phenomenon of exceeded CBM, the gas molecular has a significant chance existing in a low bond energy of chemical bonds of coal structure.
文摘Enterprises engaging in collaboration with competitors can increase their technological diversity and release a new product innovation, but also full of challenges. This complexity of co-opetition relationship requirements academia and enterprises to clarify the problem of competitive technology alliance risk formation mechanism, making the risk control to dispose. Based on the perspective of resources and capabilities, this paper firstly puts forward the double helix model of alliances＇ evolution on resources and capabilities ; then, with the deepe- ning of the cooperation, this evolutionary process leads to different innovation risk： opportunism, R and D inte- gration risk and flexible loss risk; next, analyzing the corresponding management path and constructing the conceptual framework of risk management mechanism to help enterprise using the co-opetition relationship to reduce risk and improve the potential competitive advantage.
基金supported by the National Natural Science Foundation of China (No.62373224,62333013,and U23A20327)。
文摘With the increasing attention paid to battery technology,the microscopic reaction mechanism and macroscopic heat transfer process of lithium-ion batteries have been further studied and understood from both academic and industrial perspectives.Temperature,as one of the key parameters in the physical fra mework of batteries,affects the performa nce of the multi-physical fields within the battery,a nd its effective control is crucial.Since the heat generation in the battery is determined by the real-time operating conditions,the battery temperature is essentially controlled by the real-time heat dissipation conditions provided by the battery thermal management system.Conventional battery thermal management systems have basic temperature control capabilities for most conventional application scenarios.However,with the current development of la rge-scale,integrated,and intelligent battery technology,the adva ncement of battery thermal management technology will pay more attention to the effective control of battery temperature under sophisticated situations,such as high power and widely varied operating conditions.In this context,this paper presents the latest advances and representative research related to battery thermal management system.Firstly,starting from battery thermal profile,the mechanism of battery heat generation is discussed in detail.Secondly,the static characteristics of the traditional battery thermal management system are summarized.Then,considering the dynamic requirements of battery heat dissipation under complex operating conditions,the concept of adaptive battery thermal management system is proposed based on specific research cases.Finally,the main challenges for battery thermal management system in practice are identified,and potential future developments to overcome these challenges are presented and discussed.
基金supported by the National Natural Science Foundation of China(Grant Nos.42130802 and 42372200)China Postdoctoral Science Foundation(No.2022M713792)+1 种基金Key Science and Technology Program of Shaanxi Province(No.2023YBGY-083)Open Fund of Key Laboratory of Coalbed Methane Resources and Reservoir Formation Process of the Ministry of Education(China University of Mining and Technology)(No.2022-007).
文摘The south-western Ordos Basin is rich in low-middle rank coalbed methane(CBM)resources;while the geochemical characteristics and genetic mechanism of CBM are not clear.Herein,according to geological and geochemical test data from gas and coal seam water from CBM wells in Bingchang,Jiaoxun,Huangling,Yonglong,and Longdong minging areas,we systematically studied the geochemical characteristics,generation,and evolution mechanism of CBM in Jurassic Yan’an Formation in the south-western Ordos Basin.The results show that the CH4 content of whole gas is in the range of 42.01%-94.72%.The distribution ranges of theδ^(13)C-CH_(4)value is−87.2‰to−32.5‰,indicating diverse sources of thermogenic gas and biogenic gas.The microbial methane is mainly generated by a CO_(2)reduction pathway,with certain methyl-type fermentation spots.Theδ^(13)C-CH_(4)has a positive correlation with burial depth,indicating the obvious fractionation of CBM.The relationship between the genetic types and burial depth of the CBM reservoir indicates that the favorable depth of secondary biogenic gas is less than 660 m.The Late Cretaceous Yanshanian Movement led to the uplift of the Ordos Basin,and a large amount of thermogenic gas escaped from the edge of the basin.Since the Paleogene Period,the coal reservoir in the basin margin has received recharge from atmospheric precipitation,which is favorable for the formation of secondary biogenic methane.The deep area,generally under 1000 m,mainly contains residual thermogenic gas.The intermediate transition zone is mixed gas.Constrained by the tectonic background,the genetic types of CBM in different mining areas are controlled by the coupling of burial depth,coal rank,and hydrogeological conditions.The Binchang mining area contains biogenic gas,and the development of CBM has achieved initial success,indicating that similar blocks with biogenic gas formation conditions is key to the efficient development of CBM.The research results provide a scientific basis for searching for favorable exploration areas of CBM in the south-western Ordos Basin.
基金supported by the National Key Research and Development Program of China(Grant No.2022YFF0800304)the Science and Technology Project of China National Petroleum Corporation(Grant No.2024DJ93)the Basic Research and Strategic Reserve Technology Research Project of China National Petroleum Corporation(Grant No.2020D-5008-01)。
文摘As a potential renewable and clean energy source,the distribution and exploration prospects of natural hydrogen have garnered widespread attention.However,the limitations in understanding the formation mechanisms and accumulation patterns of underground natural hydrogen have significantly constrained its efficient exploration and utilization.This study reports H_(2)content and isotopes in natural gas from deep formations in sedimentary basins through geochemical analysis of 58 conventional gas samples from the Sinian to Triassic strata in the central Sichuan Basin.We discovered that H_(2)content in deep natural gas in central Sichuan generally exceeds 0.1%,with a maximum of 1.6%,and hydrogen isotopes(δ^(2)H_(H_(2)))range from-850‰to-586‰.Analysis of the geological conditions,hydrogen generation mechanisms,and isotope fractionation characteristics in the study area confirms that microbial fermentation or in-situ organic matter cracking are not effective pathways for deep H_(2)generation.Combined with helium content and isotope analysis of the natural gas,it is inferred that the volcanic basement in the central Sichuan area is the potential source rock for natural H_(2)in the Sinian to Triassic strata.Specifically,H_(2)originates from the radiolysis of water and hydrothermal reactions of Fe(Ⅱ)in the basement granite.Additionally,a diffusion fractionation model reveals significant isotope fractionation during the migration and accumulation of deep H_(2)into sedimentary reservoirs,which lead to anomalously light δ^(2)H_(H_(2))in deep natural gas in central Sichuan.This indicates that the underground natural hydrogen accumulation is in a long-term dynamic process,with simultaneous H_(2)accumulation and dissipation in the gas reservoirs.This research not only elucidates the formation mechanism of deep H_(2)but also provides insights for the resource potential of natural hydrogen in sedimentary basins.
基金Science and Technology Planning Project of Sichuan Province with Grant No.2023YFS0429supported by Science and Technology Project of China Road and Bridge Corporation with Grant No.P2220447+1 种基金supported by Foundation of Xinjiang Institute of Engineering 2024(Grant No.2024xgy072605)supported by Sichuan Natural Science Foundation Project(Grant No.2024NSFSC0162).The numerical calculations in this study have been done on Hefei advanced computing center.
文摘In recent years,tuned liquid dampers(TLDs)have attracted significant research interest;however,overall progress has been limited due to insufficient understanding of the mechanisms governing sloshing-induced loads.In particular,it remains unclear whether the water in aqueducts—common water-diversion structures in many countries—can serve as an effective TLD.This study investigates the generation mechanisms of sloshing loads during the first-order transverse resonance of water in a U-shaped aqueduct using a two-dimensional(2D)numerical model.The results reveal that,at the equilibrium position,the free surface difference between the left and right walls,the horizontal force on the aqueduct,and the fluctuating component of the vertical force all reach their maxima,with energy predominantly stored as potential energy.At the maximum displacement position,the surface difference and horizontal force drop to zero,while the fluctuating vertical force attains its minimum and energy shifts primarily to kinetic form.At this stage,static pressure is governed solely by the vertical convective acceleration,whereas at equilibrium it is closely linked to both the free surface difference and vertical local acceleration of the water.This dynamic energy exchange generates vertical force oscillations even when the free surface appears nearly symmetric.
基金Supported by National Natural Science Foundation of China(50907046)
文摘The filter capacitor stack is one of the main acoustic noise sources in high-voltage DC(HVDC) converter stations.As HVDC systems are built more and more recently,it is significant to research the audible noise of filter capacitors.In this paper,the current situation of research on vibration and audible noise of filter capacitors in HVDC converter stations,which is departed into three parts—generation mechanism,prediction methods,and reduction measures,is presented and the research achievements are discussed.Scholars have built the model that the alternating electric force caused by the voltage conduces to the vibration,which propagates to the enclosure and radiates audible noise.As a result,the parts contributing most to the generation of audible noise are the top and the bottom of capacitors. In the noise level prediction respect,several methods have been prospected including impact hammer,sweep frequency, impact current,monopole and Kirchhoff formula method,which are suitable for single capacitors or capacitors stacks individually.However,the sweep frequency method is restricted by experiment condition,and the impact current method needs further research and verified.On the other hand,CIGRE WG14.26 provides three sound reduction measures,but all of them are not so practicable,while MPP absorber and compressible space absorber prospected by Dr.Wu Peng are proved to be effective.The sound barriers are also considered by scholars,and the acoustic directivity performance of capacitors is also researched.Besides,the developing direction of each research field is prospected in corresponding part.
基金Supported by Japan Society for the Promotion of Science(Grant Nos.14J04115,16K17990)
文摘Tailored surface textures at the micro- or nanoscale dimensions are widely used to get required functional performances. Rotary ultrasonic texturing （RUT） technique has been proved to be capable of fabricating periodic micro- and nanostructures. In the present study, diamond tools with geometrically defined cutting edges were designed for fabricating different types of tailored surface textures using the RUT method. Surface generation mechanisms and machinable structures of the RUT process are analyzed and simulated with a 3D-CAD program. Textured surfaces generated by using a triangular pyramid cutting tip are constructed. Different textural patterns from several micrometers to several tens of micrometers with few burrs were successfully fabricated, which proved that tools with a proper two-rake-face design are capable of removing cutting chips efficiently along a sinusoidal cutting locus in the RUT process. Technical applications of the textured surfaces are also discussed. Wetting properties of textured aluminum surfaces were evaluated by combining the test of surface roughness features. The results show that the real surface area of the textured aluminum surfaces almost doubled by comparing with that of a flat surface, and anisotropic wetting properties were obtained due to the obvious directional textural features.
