Minimum quantity Lubrication(MQL)is a sustainable lubrication system that is famous in many machining systems.It involve the spray of an infinitesimal amount of mist-like lubricants during machining processes.The MQL ...Minimum quantity Lubrication(MQL)is a sustainable lubrication system that is famous in many machining systems.It involve the spray of an infinitesimal amount of mist-like lubricants during machining processes.The MQL system is affirmed to exhibit an excellent machining performance,and it is highly economical.The nanofluids are understood to exhibit excellent lubricity and heat evacuation capability,compared to pure oil-based MQL system.Studies have shown that the surface quality and amount of energy expended in the grinding operations can be reduced considerably due to the positive effect of these nanofluids.This work presents an experimental study on the tribological performance of SiO_(2)nanofluid during grinding of Si_(3)N_(4)ceramic.The effect different grinding modes and lubrication systems during the grinding operation was also analyzed.Different concentrations of the SiO_(2)nanofluid was manufactured using canola,corn and sunflower oils.The quantitative evaluation of the grinding process was done based on the amount of grinding forces,specific grinding energy,frictional coefficient,and surface integrity.It was found that the canola oil exhibits optimal lubrication performance compared to corn oil,sunflower oil,and traditional lubrication systems.Additionally,the introduction of ultrasonic vibrations with the SiO_(2)nanofluid in MQL system was found to reduce the specific grinding energy,normal grinding forces,tangential grinding forces,and surface roughness by 65%,57%,65%,and 18%respectively.Finally,regression analysis was used to obtain an optimum parameter combinations.The observations from this work will aid the smooth transition towards ecofriendly and sustainable machining of engineering ceramics.展开更多
Because of the various elements that come into play in natural soil formation, the impact of varied proportions of mineral composition and fines amount on Atterberg limits and compaction characteristics of soils is no...Because of the various elements that come into play in natural soil formation, the impact of varied proportions of mineral composition and fines amount on Atterberg limits and compaction characteristics of soils is not well known. Three distinct soil samples were used in this investigation. The findings indicated the effect of varied mineral composition proportions and fines amount on the liquid limit, plastic limit, and plasticity index as assessed by the Casagrande test and hand-rolling method. The fluctuation of maximum dry density and optimal moisture content with these three soils has also been studied. Furthermore, correlations were established to indicate the compaction parameters and the amount of minerals and particles in the soil. The data show that the mineral content of the soil has a direct impact on the Atterberg limits and compaction characteristics. Soils containing larger percentages of expansive minerals, such as montmorillonite, have more flexibility and volume change capability. Mineral composition influences compaction parameters such as maximum dry density, ideal water content, axial strain, and axial stress. Soils with a larger proportion of fines, such as Soil 2 and Soil 3, have stronger flexibility and lower compaction qualities, with higher ideal water content and lower maximum dry density. Soil 1 has moderate flexibility and intermediate compaction qualities due to its low fines percentage. The effect of different mineral compositions and fines on the Atterberg limits and compaction characteristics of soils can be used to predict the behavior of compacted soils encountered in engineering practices, reducing the time and effort required to assess soil suitability for engineering use.展开更多
Traditional methods for selecting models in experimental data analysis are susceptible to researcher bias, hindering exploration of alternative explanations and potentially leading to overfitting. The Finite Informati...Traditional methods for selecting models in experimental data analysis are susceptible to researcher bias, hindering exploration of alternative explanations and potentially leading to overfitting. The Finite Information Quantity (FIQ) approach offers a novel solution by acknowledging the inherent limitations in information processing capacity of physical systems. This framework facilitates the development of objective criteria for model selection (comparative uncertainty) and paves the way for a more comprehensive understanding of phenomena through exploring diverse explanations. This work presents a detailed comparison of the FIQ approach with ten established model selection methods, highlighting the advantages and limitations of each. We demonstrate the potential of FIQ to enhance the objectivity and robustness of scientific inquiry through three practical examples: selecting appropriate models for measuring fundamental constants, sound velocity, and underwater electrical discharges. Further research is warranted to explore the full applicability of FIQ across various scientific disciplines.展开更多
Nanofluid minimum quantity lubrication(NMQL)is a green processing technology.Cottonseed oil is suitable as base oil because of excellent lubrication performance,low freezing temperature,and high yield.Al_(2)O_(3)nanop...Nanofluid minimum quantity lubrication(NMQL)is a green processing technology.Cottonseed oil is suitable as base oil because of excellent lubrication performance,low freezing temperature,and high yield.Al_(2)O_(3)nanoparticles improve not only the heat transfer capacity but also the lubrication performance.The physical and chemical proper-ties of nanofluid change when Al_(2)O_(3)nanoparticles are added.However,the effects of the concentration of nanofluid on lubrication performance remain unknown.Furthermore,the mechanisms of interaction between Al_(2)O_(3)nanoparti-cles and cottonseed oil are unclear.In this research,nanofluid is prepared by adding different mass concentrations of Al_(2)O_(3)nanoparticles(0,0.2%,0.5%,1%,1.5%,and 2%wt)to cottonseed oil during minimum quantity lubrication(MQL)milling 45 steel.The tribological properties of nanofluid with different concentrations at the tool/workpiece interface are studied through macro-evaluation parameters(milling force,specific energy)and micro-evaluation parameters(surface roughness,micro morphology,contact angle).The result show that the specific energy is at the minimum(114 J/mm^(3)),and the roughness value is the lowest(1.63μm)when the concentration is 0.5 wt%.The surfaces of the chip and workpiece are the smoothest,and the contact angle is the lowest,indicating that the tribological proper-ties are the best under 0.5 wt%.This research investigates the intercoupling mechanisms of Al_(2)O_(3)nanoparticles and cottonseed base oil,and acquires the optimal Al_(2)O_(3)nanofluid concentration to receive satisfactory tribological properties.展开更多
Graphene has superhigh thermal conductivity up to 5000 W/(m·K),extremely thin thickness,superhigh mechanical strength and nano-lamellar structure with low interlayer shear strength,making it possess great potenti...Graphene has superhigh thermal conductivity up to 5000 W/(m·K),extremely thin thickness,superhigh mechanical strength and nano-lamellar structure with low interlayer shear strength,making it possess great potential in mini-mum quantity lubrication(MQL)grinding.Meanwhile,ionic liquids(ILs)have higher thermal conductivity and better thermal stability than vegetable oils,which are frequently used as MQL grinding fluids.And ILs have extremely low vapor pressure,thereby avoiding film boiling in grinding.These excellent properties make ILs also have immense potential in MQL grinding.However,the grinding performance of graphene and ionic liquid mixed fluid under nano-fluid minimum quantity lubrication(NMQL),and its tribological mechanism on abrasive grain/workpiece grinding interface,are still unclear.This research firstly evaluates the grinding performance of graphene and ionic liquid mixed nanofluids(graphene/IL nanofluids)under NMQL experimentally.The evaluation shows that graphene/IL nanofluids can further strengthen both the cooling and lubricating performances compared with MQL grinding using ILs only.The specific grinding energy and grinding force ratio can be reduced by over 40%at grinding depth of 10μm.Work-piece machined surface roughness can be decreased by over 10%,and grinding temperature can be lowered over 50℃at grinding depth of 30μm.Aiming at the unclear tribological mechanism of graphene/IL nanofluids,molecular dynamics simulations for abrasive grain/workpiece grinding interface are performed to explore the formation mechanism of physical adsorption film.The simulations show that the grinding interface is in a boundary lubrication state.IL molecules absorb in groove-like fractures on grain wear flat face to form boundary lubrication film,and graphene nanosheets can enter into the grinding interface to further decrease the contact area between abrasive grain and workpiece.Compared with MQL grinding,the average tangential grinding force of graphene/IL nanofluids can decrease up to 10.8%.The interlayer shear effect and low interlayer shear strength of graphene nanosheets are the principal causes of enhanced lubricating performance on the grinding interface.EDS and XPS analyses are further carried out to explore the formation mechanism of chemical reaction film.The analyses show that IL base fluid happens chemical reactions with workpiece material,producing FeF_(2),CrF_(3),and BN.The fresh machined surface of workpiece is oxidized by air,producing NiO,Cr_(2)O_(3) and Fe_(2)O_(3).The chemical reaction film is constituted by fluorides,nitrides and oxides together.The combined action of physical adsorption film and chemical reaction film make graphene/IL nano-fluids obtain excellent grinding performance.展开更多
A qualia role-based entity-dependency graph(EDG)is proposed to represent and extract quantity relations for solving algebra story problems stated in Chinese.Traditional neural solvers use end-to-end models to translat...A qualia role-based entity-dependency graph(EDG)is proposed to represent and extract quantity relations for solving algebra story problems stated in Chinese.Traditional neural solvers use end-to-end models to translate problem texts into math expressions,which lack quantity relation acquisition in sophisticated scenarios.To address the problem,the proposed method leverages EDG to represent quantity relations hidden in qualia roles of math objects.Algorithms were designed for EDG generation and quantity relation extraction for solving algebra story problems.Experimental result shows that the proposedmethod achieved an average accuracy of 82.2%on quantity relation extraction compared to 74.5%of baseline method.Another prompt learning result shows a 5%increase obtained in problem solving by injecting the extracted quantity relations into the baseline neural solvers.展开更多
Regressive formulae to calculate the quantity of plant leaf area for 13 species of ornamental plants were set up based on investigation data of 30 species on 3 major public squares (Dongfeng square, Shengli square and...Regressive formulae to calculate the quantity of plant leaf area for 13 species of ornamental plants were set up based on investigation data of 30 species on 3 major public squares (Dongfeng square, Shengli square and Guandu square) in Kun-ming City, China, which were applied to calculate quantities of plant leaf area of these 13 species. The quantities of plant leaf area for the other 17 ornamental plant species on these squares were directly measured, and the total quantity of plant leaf area of each studied square was obtained individually. The results showed that the quantity of plant leaf area on Shengli square with ornamental plants structure composed of arbor tree species, shrub tree species and turf grass was highest among the three squares. It is believed that the design model of multi-storied vertical structure and proper tending of plant community could not only increase the quantity of plant leaf area, but also play an important role in generating ecological and landscaping benefits. Some corresponding suggestions were put forward on the basis of comprehensive analyses on the plant leaf area quantity of the three representative squares in Kunming urban area.展开更多
[Objective] The aim was to research the rules of nectar quantity and sugar concentration of perfect and staminate flowers in a day. [Method] Based on nine Tianguang Yan pomegranate trees, nectar quantity and sugar con...[Objective] The aim was to research the rules of nectar quantity and sugar concentration of perfect and staminate flowers in a day. [Method] Based on nine Tianguang Yan pomegranate trees, nectar quantity and sugar concentration of per- fect and staminate flowers were measured and analyzed in morning and afternoon. [Result] Average nectar quantity and sugar concentration differed insignificantly in morning and afternoon of perfect flowers, which could also be applied to staminate flowers. However, average nectar quantity of perfect flower was 64.09 μI and of staminate flower was 44.07 μl. It is obvious that the two were of extremely signifi- cant differences (t=4.642, P〈0.01), and the former was significantly higher by 45,43%. On the other hand, average sugar concentration of perfect flower was 48.44% and of staminate flower was 37.16%. The two were of extremely significant differences and the former is higher by 30.36%, compared with the latter. These suggested that nectar quantity and sugar concentration would maintain unchanged in different periods for a day, if nectars are not consumed by pollinators, such as bees and butterflies. In the same period, nectar quantity and sugar concentration of per- fect flowers were higher than those of staminate flowers. [Conclusion] The research provides references for benefits increase of bee farmers and fruit farmers, as well as exploration of bee pollination.展开更多
Mongolia,a key partner in the Belt and Road Initiative,is fully dedicated to fostering regional cooperation and connectivity.Standardization has emerged as a vital field with far-reaching influence for regional trade ...Mongolia,a key partner in the Belt and Road Initiative,is fully dedicated to fostering regional cooperation and connectivity.Standardization has emerged as a vital field with far-reaching influence for regional trade cooperation.This paper makes an in-depth analysis of the standards approved in Mongolia in 2021 and 2022,offering a fresh perspective of the past two years’standardization development in the country.The primary objective is to present an updated account of Mongolia’s standardization efforts and to facilitate regional cooperation and exchange in standardization.展开更多
[Objective] This study aimed to investigate the effects of different land use patterns on soil ecological environment. [Method] Total three representative land use patterns (corn field, cherry tree land, wood land) ...[Objective] This study aimed to investigate the effects of different land use patterns on soil ecological environment. [Method] Total three representative land use patterns (corn field, cherry tree land, wood land) were selected from Hongta District, Yuxi City, and under these three patterns, soil microbial quantity and activity were studied. [Result] Under the three land use patterns, soil microorganisms were domi- nated by bacteria; soil microbial quantity ranked as wood land's〉cheery tree land's〉 corn field's; and total microbial activity, catalase activity and urease activity all ranked as cherry tree land's〉wood land's〉corn field's. [Conclusion] Soil microbial activity and functions are related to farmland management measures, as well as land use pattern and soil nutrients.展开更多
OBJECTIVE To investigate the changes and values of the expression of α-tubulin and γ-tubulin in atypical ductal hyperplasia (ADH), ductal carcinoma in situ (DCIS) and invasive ductal carcinoma (IDC) of the bre...OBJECTIVE To investigate the changes and values of the expression of α-tubulin and γ-tubulin in atypical ductal hyperplasia (ADH), ductal carcinoma in situ (DCIS) and invasive ductal carcinoma (IDC) of the breast. The relationship between centrosome abnormalities and breast tumor development was further discussed. METHODS There were three groups including ADH, DCIS and IDC with 30 cases in each group. They were analyzed by immuno-fiuorescence quantity analysis. The expression levels of α-tubulin and γ-tubulin protein in these tissues were detected by flow cytometry immuno-fiuorescence analysis and compared with the results from normal tissues. Immunohistochemistry was also performed in this research. RESULTS The results showed significant differences of the average of the positive (FITC labeled) cells (P=0.000) among the four groups. The level of the IDC group was the highest, while normal breast tissue showed the lowest level. The results suggested that the expression levels of α-tubulin and γ-tubulin both increased as the grade of cellular proliferation and differentiation increased. The expressions showed significant differences among all the groups, except between the ADH and DCIS. There were no significant differences between α-tubulin and γ-tubulin expression in each group (P〈0.05), as there was agreement in the immuno-fluorescence and immunohistochemical analysis for protein expression. CONCLUSION There is abnormal expression of centrosome tubulin as an early event in the development of breast tumor. Furthermore these aberrations may play a key role during oncogenesis and promote cellular transformation to malignancy. The immuno-fiuorescence quantitive analysis and immunohistochemistry can complement each other.展开更多
Background:Soil acidifcationn caused by anthropogenic activities may aft soil biochemical cydling,bidiversity,productivity,and multiple eosystem-related functions in drylands.However,to date,such information is lackin...Background:Soil acidifcationn caused by anthropogenic activities may aft soil biochemical cydling,bidiversity,productivity,and multiple eosystem-related functions in drylands.However,to date,such information is lacking to support this hypothesis.Methods Based on a transect survey of 78 naturally assembled shrub communities,we caloulated acid deposition flux in Northwest China and evaluated its likely ecological ffets by testing three altemnative hypotheses,namely:.nidche complementarity,mass ratio,and vegetation quantity hypotheses Rao's quadratic entopy and community-weighted mean traits were employed to represent the complementary aspect of niche complementarity and mass ratio effects,respectively.Resulbs:We observed that in the past four decades,the concentrations of exchangeable base cations in soil in Northwest China have decreased significantly to the extent of having faced the risk of depletion,whereas changes in the calium carbonate content and pH of soil were not significant.Adid deposition primani ly increased the aboweground biomass and shrub density in shrublands but had no sigmificant effect on shrub richness and ecasystem multifunctionality(EMF),indicating that acid deposition had positive but weak ecological effects on dryland ecosystems.Community wd ghted mean of functional traits(representing the mass ratio hypothesis)correlated negatively with EMF,whereas both Rao's quadratic entropy(representing the niche complementarity hypothesis)and aboveground biomass(representing the vegetation quantity hypothesis)correlated positively but insignifcantly with EMF.These biodiversity-EMF relationships highlight the fragility and instability of drylands relative to forest ecasystems.Concuions:The findings from this study serve as important reference points to understand the ris of soil acidification in arid regions and its impacts on biodiversity-EMF relationships.展开更多
[Objective] The aim was to research the appropriate seeding quantities of double-season machine-transplanted rice in middle and low-yielding district of southern Jiangxi Province. [Method] The research set five differ...[Objective] The aim was to research the appropriate seeding quantities of double-season machine-transplanted rice in middle and low-yielding district of southern Jiangxi Province. [Method] The research set five different seeding quantities treatments, and compared with conventional seedling treatment, and the appropriate seeding quantities of double season machine-transplanted rice in middle and lowyielding district of southern Jiangxi Province was discussed. [Result] The yields were highest when the seeding quantity was 70 g per tray of early rice by mechanical transplanting and 60 g per tray of late rice. The yield of early rice by mechanical transplanting showed significantly positive correlation with the number of productive ear and the number of seed per ear, and late rice yield showed significant correlation with the number of productive ear by mechanical transplanting. It is key for improving high yields by guaranteeing the number of productive ear. [Conclusion] The issue of proper sowing quantity should be taken into consideration for double-cropping rice in the region, which is crucial for high yields.展开更多
In this article, the names of 3 varieties of Monarda didyma L., which are considered to be introduced species, some indicators of the water regime in the climatic conditions of Uzbekistan: the amount of water in the l...In this article, the names of 3 varieties of Monarda didyma L., which are considered to be introduced species, some indicators of the water regime in the climatic conditions of Uzbekistan: the amount of water in the leaves, water deficit, water storage capacity were studied in spring and summer, and seasonal changes were determined. According to these indicators of the water regime, the studied varieties belong to the labile water regime, high green mass (centner), seed yield (how many grams), resistance to diseases and pests have been determined, which shows that it is promising for introduction in the conditions of our republic. Therefore, it is recommended to breed these varieties in the foothills and hilly regions of Uzbekistan, where the amount of precipitation is more than 400 - 500 mm.展开更多
Objective] The alm was to provide scientific references for determination of optimal N and P quantities of malze. [Method] The research conducted a test in field to expIore the effects of N and P fertiIizers on malze ...Objective] The alm was to provide scientific references for determination of optimal N and P quantities of malze. [Method] The research conducted a test in field to expIore the effects of N and P fertiIizers on malze yield. [Result] Both of N and P fertiIizers have significant effects on malze yield. When malze yield reached the highest, the quantities of N fertiIizers and P fertiIizers were 530.56 and 105.44 kg/hm2, respectiveIy. [Conclusion] Malze yield keeps growing upon N or P fertiIizers to certaln extent, and excessive quantities of N and P fertiIizer wouId reduce malze yield.展开更多
The presented work examines the mechanism and conditions of self-motion in bodies as systems of interacting elements. It is shown how the oscillation parameters of these elements determine the mode of motion of the sy...The presented work examines the mechanism and conditions of self-motion in bodies as systems of interacting elements. It is shown how the oscillation parameters of these elements determine the mode of motion of the system (body). In this case, the motion is considered as a consequence of symmetry breaking of forces in the systems themselves, and not as a reaction of individual elements to external influences. It is shown that such a violation takes place both in the gravitational field and when the system moves by inertia. Examples of the influence of changes in phase (φ) and frequency (f) parameters of the system elements on the velocity mode of its motion in space are considered. The identity of the causes of self-motion is revealed both in the case of gravitation and inertial motion.展开更多
Widespread changes to forested watersheds affected by the mountain pine beetle (Dendroctonus ponderosae Hopkins) epidemic across western North America raised concerns about the effects of this climate-induced disturba...Widespread changes to forested watersheds affected by the mountain pine beetle (Dendroctonus ponderosae Hopkins) epidemic across western North America raised concerns about the effects of this climate-induced disturbance on drinking water and natural resources. Effective communication and knowledge exchange across scientists and stakeholders (i.e., drinking water managers) is essential for constructively responding to such landscape scale disturbances, providing improved adaptive capacity through knowledge sharing. An assessment of stakeholder knowledge levels, information needs, primary concerns, and suggested communication strategies were conducted via an online elicitation survey and World Science Café workshops. Knowledge levels, assessed via a survey of local water managers and experts, were relatively low with approximately half of the respondents reporting little to no knowledge of the effects of mountain pine beetle on drinking water quality and quantity, thereby indicating limited knowledge exchange between scientists and drinking water stakeholders. Increased accessibility and dissemination of research findings pertinent to the mountain pine beetle epidemic’s effects on drinking water quality and quantity is necessary for natural resource management. Recommendations for improved communication among scientists and drinking water stakeholders in particular and forest health in general include dispersal of non-academic research summaries, information exchange through existing media and community resources, demonstration projects, and information clearinghouses. This information provides a better understanding of the challenges, concerns, and first-hand experience of stakeholders of a landscape disturbance issue to apply this knowledge to enhance land management practice and how researchers on this overall project enhanced science communication efforts.展开更多
The main purpose of this paper is to generalize the effect of two-phased demand and variable deterioration within the EOQ (Economic Order Quantity) framework. The rate of deterioration is a linear function of time. Th...The main purpose of this paper is to generalize the effect of two-phased demand and variable deterioration within the EOQ (Economic Order Quantity) framework. The rate of deterioration is a linear function of time. The two-phased demand function states the constant function for a certain period and the quadratic function of time for the rest part of the cycle time. No shortages as well as partial backlogging are allowed to occur. The mathematical expressions are derived for determining the optimal cycle time, order quantity and total cost function. An easy-to-use working procedure is provided to calculate the above quantities. A couple of numerical examples are cited to explain the theoretical results and sensitivity analysis of some selected examples is carried out.展开更多
The development and deployment of privary preserving supply chain quantity discount contract design can allow supply chain collaborations to take place without revealing any participant's data to others, reaping the ...The development and deployment of privary preserving supply chain quantity discount contract design can allow supply chain collaborations to take place without revealing any participant's data to others, reaping the benefits of collaborations wbile avoiding the drawbacks of privacy information disclosure. First, secure multi-party computation protocols are applied in the joint-ordering policy between a single supplier and a single retailer, the joint-ordering policy can be conducted without disclosing private cost information of any of the other supply chain partners. Secondly, secure multi-party computation protocols are applied in the privacy preserving supply chain quantity discount contract design between a single supplier and a single retailer. The information disclosure analyses of the algorithm show that: the optimal quantity discount of the jointordering policy can be conducted without disclosing private cost information of any of the other supply chain partners; the above protocol can be implemented without mediators; the privacy preserving quantity discount algorithm can be mutually verifiable and has solved the problem of asymmetric information.展开更多
Urban peripheral green space (UPGS) plays more and more important rol e in sustaining urban physical and ecological environments. In this paper, a pre liminary classification of UPGS was presented for seven types and ...Urban peripheral green space (UPGS) plays more and more important rol e in sustaining urban physical and ecological environments. In this paper, a pre liminary classification of UPGS was presented for seven types and quantity index of UPGS was discussed tentatively. The quantity and layout problems in urban pe ripheral green space, and the several principles were mainly discussed in urban ventilation and sanitation, recreational opportunity and landscape ecological st ructure.展开更多
文摘Minimum quantity Lubrication(MQL)is a sustainable lubrication system that is famous in many machining systems.It involve the spray of an infinitesimal amount of mist-like lubricants during machining processes.The MQL system is affirmed to exhibit an excellent machining performance,and it is highly economical.The nanofluids are understood to exhibit excellent lubricity and heat evacuation capability,compared to pure oil-based MQL system.Studies have shown that the surface quality and amount of energy expended in the grinding operations can be reduced considerably due to the positive effect of these nanofluids.This work presents an experimental study on the tribological performance of SiO_(2)nanofluid during grinding of Si_(3)N_(4)ceramic.The effect different grinding modes and lubrication systems during the grinding operation was also analyzed.Different concentrations of the SiO_(2)nanofluid was manufactured using canola,corn and sunflower oils.The quantitative evaluation of the grinding process was done based on the amount of grinding forces,specific grinding energy,frictional coefficient,and surface integrity.It was found that the canola oil exhibits optimal lubrication performance compared to corn oil,sunflower oil,and traditional lubrication systems.Additionally,the introduction of ultrasonic vibrations with the SiO_(2)nanofluid in MQL system was found to reduce the specific grinding energy,normal grinding forces,tangential grinding forces,and surface roughness by 65%,57%,65%,and 18%respectively.Finally,regression analysis was used to obtain an optimum parameter combinations.The observations from this work will aid the smooth transition towards ecofriendly and sustainable machining of engineering ceramics.
文摘Because of the various elements that come into play in natural soil formation, the impact of varied proportions of mineral composition and fines amount on Atterberg limits and compaction characteristics of soils is not well known. Three distinct soil samples were used in this investigation. The findings indicated the effect of varied mineral composition proportions and fines amount on the liquid limit, plastic limit, and plasticity index as assessed by the Casagrande test and hand-rolling method. The fluctuation of maximum dry density and optimal moisture content with these three soils has also been studied. Furthermore, correlations were established to indicate the compaction parameters and the amount of minerals and particles in the soil. The data show that the mineral content of the soil has a direct impact on the Atterberg limits and compaction characteristics. Soils containing larger percentages of expansive minerals, such as montmorillonite, have more flexibility and volume change capability. Mineral composition influences compaction parameters such as maximum dry density, ideal water content, axial strain, and axial stress. Soils with a larger proportion of fines, such as Soil 2 and Soil 3, have stronger flexibility and lower compaction qualities, with higher ideal water content and lower maximum dry density. Soil 1 has moderate flexibility and intermediate compaction qualities due to its low fines percentage. The effect of different mineral compositions and fines on the Atterberg limits and compaction characteristics of soils can be used to predict the behavior of compacted soils encountered in engineering practices, reducing the time and effort required to assess soil suitability for engineering use.
文摘Traditional methods for selecting models in experimental data analysis are susceptible to researcher bias, hindering exploration of alternative explanations and potentially leading to overfitting. The Finite Information Quantity (FIQ) approach offers a novel solution by acknowledging the inherent limitations in information processing capacity of physical systems. This framework facilitates the development of objective criteria for model selection (comparative uncertainty) and paves the way for a more comprehensive understanding of phenomena through exploring diverse explanations. This work presents a detailed comparison of the FIQ approach with ten established model selection methods, highlighting the advantages and limitations of each. We demonstrate the potential of FIQ to enhance the objectivity and robustness of scientific inquiry through three practical examples: selecting appropriate models for measuring fundamental constants, sound velocity, and underwater electrical discharges. Further research is warranted to explore the full applicability of FIQ across various scientific disciplines.
基金Supported by National Natural Science Foundation of China(Grant Nos.51806112,51975305)PhD Research Startup Foundation of Qingdao University of Technology,China(Grant Nos.JC2022-012,20312008).
文摘Nanofluid minimum quantity lubrication(NMQL)is a green processing technology.Cottonseed oil is suitable as base oil because of excellent lubrication performance,low freezing temperature,and high yield.Al_(2)O_(3)nanoparticles improve not only the heat transfer capacity but also the lubrication performance.The physical and chemical proper-ties of nanofluid change when Al_(2)O_(3)nanoparticles are added.However,the effects of the concentration of nanofluid on lubrication performance remain unknown.Furthermore,the mechanisms of interaction between Al_(2)O_(3)nanoparti-cles and cottonseed oil are unclear.In this research,nanofluid is prepared by adding different mass concentrations of Al_(2)O_(3)nanoparticles(0,0.2%,0.5%,1%,1.5%,and 2%wt)to cottonseed oil during minimum quantity lubrication(MQL)milling 45 steel.The tribological properties of nanofluid with different concentrations at the tool/workpiece interface are studied through macro-evaluation parameters(milling force,specific energy)and micro-evaluation parameters(surface roughness,micro morphology,contact angle).The result show that the specific energy is at the minimum(114 J/mm^(3)),and the roughness value is the lowest(1.63μm)when the concentration is 0.5 wt%.The surfaces of the chip and workpiece are the smoothest,and the contact angle is the lowest,indicating that the tribological proper-ties are the best under 0.5 wt%.This research investigates the intercoupling mechanisms of Al_(2)O_(3)nanoparticles and cottonseed base oil,and acquires the optimal Al_(2)O_(3)nanofluid concentration to receive satisfactory tribological properties.
基金Supported by Shandong Provincial Natural Science Foundation of China(Grant Nos.ZR2022ME208,ZR2020QE181)National Natural Science Foundation of China(Grant Nos.51705272,52005281)+1 种基金China Postdoctoral Science Foundation(Grant No.2018M642628)111 project(Grant No.D21017).
文摘Graphene has superhigh thermal conductivity up to 5000 W/(m·K),extremely thin thickness,superhigh mechanical strength and nano-lamellar structure with low interlayer shear strength,making it possess great potential in mini-mum quantity lubrication(MQL)grinding.Meanwhile,ionic liquids(ILs)have higher thermal conductivity and better thermal stability than vegetable oils,which are frequently used as MQL grinding fluids.And ILs have extremely low vapor pressure,thereby avoiding film boiling in grinding.These excellent properties make ILs also have immense potential in MQL grinding.However,the grinding performance of graphene and ionic liquid mixed fluid under nano-fluid minimum quantity lubrication(NMQL),and its tribological mechanism on abrasive grain/workpiece grinding interface,are still unclear.This research firstly evaluates the grinding performance of graphene and ionic liquid mixed nanofluids(graphene/IL nanofluids)under NMQL experimentally.The evaluation shows that graphene/IL nanofluids can further strengthen both the cooling and lubricating performances compared with MQL grinding using ILs only.The specific grinding energy and grinding force ratio can be reduced by over 40%at grinding depth of 10μm.Work-piece machined surface roughness can be decreased by over 10%,and grinding temperature can be lowered over 50℃at grinding depth of 30μm.Aiming at the unclear tribological mechanism of graphene/IL nanofluids,molecular dynamics simulations for abrasive grain/workpiece grinding interface are performed to explore the formation mechanism of physical adsorption film.The simulations show that the grinding interface is in a boundary lubrication state.IL molecules absorb in groove-like fractures on grain wear flat face to form boundary lubrication film,and graphene nanosheets can enter into the grinding interface to further decrease the contact area between abrasive grain and workpiece.Compared with MQL grinding,the average tangential grinding force of graphene/IL nanofluids can decrease up to 10.8%.The interlayer shear effect and low interlayer shear strength of graphene nanosheets are the principal causes of enhanced lubricating performance on the grinding interface.EDS and XPS analyses are further carried out to explore the formation mechanism of chemical reaction film.The analyses show that IL base fluid happens chemical reactions with workpiece material,producing FeF_(2),CrF_(3),and BN.The fresh machined surface of workpiece is oxidized by air,producing NiO,Cr_(2)O_(3) and Fe_(2)O_(3).The chemical reaction film is constituted by fluorides,nitrides and oxides together.The combined action of physical adsorption film and chemical reaction film make graphene/IL nano-fluids obtain excellent grinding performance.
基金supported by the National Natural Science Foundation of China (Nos.62177024,62007014)the Humanities and Social Sciences Youth Fund of the Ministry of Education (No.20YJC880024)+1 种基金China Post Doctoral Science Foundation (No.2019M652678)the Fundamental Research Funds for the Central Universities (No.CCNU20ZT019).
文摘A qualia role-based entity-dependency graph(EDG)is proposed to represent and extract quantity relations for solving algebra story problems stated in Chinese.Traditional neural solvers use end-to-end models to translate problem texts into math expressions,which lack quantity relation acquisition in sophisticated scenarios.To address the problem,the proposed method leverages EDG to represent quantity relations hidden in qualia roles of math objects.Algorithms were designed for EDG generation and quantity relation extraction for solving algebra story problems.Experimental result shows that the proposedmethod achieved an average accuracy of 82.2%on quantity relation extraction compared to 74.5%of baseline method.Another prompt learning result shows a 5%increase obtained in problem solving by injecting the extracted quantity relations into the baseline neural solvers.
基金This research was sponsored by Educational Department of Yunnan Province (No. 03Z583B).
文摘Regressive formulae to calculate the quantity of plant leaf area for 13 species of ornamental plants were set up based on investigation data of 30 species on 3 major public squares (Dongfeng square, Shengli square and Guandu square) in Kun-ming City, China, which were applied to calculate quantities of plant leaf area of these 13 species. The quantities of plant leaf area for the other 17 ornamental plant species on these squares were directly measured, and the total quantity of plant leaf area of each studied square was obtained individually. The results showed that the quantity of plant leaf area on Shengli square with ornamental plants structure composed of arbor tree species, shrub tree species and turf grass was highest among the three squares. It is believed that the design model of multi-storied vertical structure and proper tending of plant community could not only increase the quantity of plant leaf area, but also play an important role in generating ecological and landscaping benefits. Some corresponding suggestions were put forward on the basis of comprehensive analyses on the plant leaf area quantity of the three representative squares in Kunming urban area.
基金Supported by National Modern Agriculture (Bee Industry) Technolgy System (CARS-45-SYZ17)~~
文摘[Objective] The aim was to research the rules of nectar quantity and sugar concentration of perfect and staminate flowers in a day. [Method] Based on nine Tianguang Yan pomegranate trees, nectar quantity and sugar concentration of per- fect and staminate flowers were measured and analyzed in morning and afternoon. [Result] Average nectar quantity and sugar concentration differed insignificantly in morning and afternoon of perfect flowers, which could also be applied to staminate flowers. However, average nectar quantity of perfect flower was 64.09 μI and of staminate flower was 44.07 μl. It is obvious that the two were of extremely signifi- cant differences (t=4.642, P〈0.01), and the former was significantly higher by 45,43%. On the other hand, average sugar concentration of perfect flower was 48.44% and of staminate flower was 37.16%. The two were of extremely significant differences and the former is higher by 30.36%, compared with the latter. These suggested that nectar quantity and sugar concentration would maintain unchanged in different periods for a day, if nectars are not consumed by pollinators, such as bees and butterflies. In the same period, nectar quantity and sugar concentration of per- fect flowers were higher than those of staminate flowers. [Conclusion] The research provides references for benefits increase of bee farmers and fruit farmers, as well as exploration of bee pollination.
文摘Mongolia,a key partner in the Belt and Road Initiative,is fully dedicated to fostering regional cooperation and connectivity.Standardization has emerged as a vital field with far-reaching influence for regional trade cooperation.This paper makes an in-depth analysis of the standards approved in Mongolia in 2021 and 2022,offering a fresh perspective of the past two years’standardization development in the country.The primary objective is to present an updated account of Mongolia’s standardization efforts and to facilitate regional cooperation and exchange in standardization.
文摘[Objective] This study aimed to investigate the effects of different land use patterns on soil ecological environment. [Method] Total three representative land use patterns (corn field, cherry tree land, wood land) were selected from Hongta District, Yuxi City, and under these three patterns, soil microbial quantity and activity were studied. [Result] Under the three land use patterns, soil microorganisms were domi- nated by bacteria; soil microbial quantity ranked as wood land's〉cheery tree land's〉 corn field's; and total microbial activity, catalase activity and urease activity all ranked as cherry tree land's〉wood land's〉corn field's. [Conclusion] Soil microbial activity and functions are related to farmland management measures, as well as land use pattern and soil nutrients.
文摘OBJECTIVE To investigate the changes and values of the expression of α-tubulin and γ-tubulin in atypical ductal hyperplasia (ADH), ductal carcinoma in situ (DCIS) and invasive ductal carcinoma (IDC) of the breast. The relationship between centrosome abnormalities and breast tumor development was further discussed. METHODS There were three groups including ADH, DCIS and IDC with 30 cases in each group. They were analyzed by immuno-fiuorescence quantity analysis. The expression levels of α-tubulin and γ-tubulin protein in these tissues were detected by flow cytometry immuno-fiuorescence analysis and compared with the results from normal tissues. Immunohistochemistry was also performed in this research. RESULTS The results showed significant differences of the average of the positive (FITC labeled) cells (P=0.000) among the four groups. The level of the IDC group was the highest, while normal breast tissue showed the lowest level. The results suggested that the expression levels of α-tubulin and γ-tubulin both increased as the grade of cellular proliferation and differentiation increased. The expressions showed significant differences among all the groups, except between the ADH and DCIS. There were no significant differences between α-tubulin and γ-tubulin expression in each group (P〈0.05), as there was agreement in the immuno-fluorescence and immunohistochemical analysis for protein expression. CONCLUSION There is abnormal expression of centrosome tubulin as an early event in the development of breast tumor. Furthermore these aberrations may play a key role during oncogenesis and promote cellular transformation to malignancy. The immuno-fiuorescence quantitive analysis and immunohistochemistry can complement each other.
基金financially supported by the third xinjiang scientific expedition program (grant no.2022xjkk0901)the Strategic Priority Research Program of Chinese Academy of Sciences (No.XDA2006030102)the National Natural Sciences Foundation of China(No.42171068 and No.42330503)。
文摘Background:Soil acidifcationn caused by anthropogenic activities may aft soil biochemical cydling,bidiversity,productivity,and multiple eosystem-related functions in drylands.However,to date,such information is lacking to support this hypothesis.Methods Based on a transect survey of 78 naturally assembled shrub communities,we caloulated acid deposition flux in Northwest China and evaluated its likely ecological ffets by testing three altemnative hypotheses,namely:.nidche complementarity,mass ratio,and vegetation quantity hypotheses Rao's quadratic entopy and community-weighted mean traits were employed to represent the complementary aspect of niche complementarity and mass ratio effects,respectively.Resulbs:We observed that in the past four decades,the concentrations of exchangeable base cations in soil in Northwest China have decreased significantly to the extent of having faced the risk of depletion,whereas changes in the calium carbonate content and pH of soil were not significant.Adid deposition primani ly increased the aboweground biomass and shrub density in shrublands but had no sigmificant effect on shrub richness and ecasystem multifunctionality(EMF),indicating that acid deposition had positive but weak ecological effects on dryland ecosystems.Community wd ghted mean of functional traits(representing the mass ratio hypothesis)correlated negatively with EMF,whereas both Rao's quadratic entropy(representing the niche complementarity hypothesis)and aboveground biomass(representing the vegetation quantity hypothesis)correlated positively but insignifcantly with EMF.These biodiversity-EMF relationships highlight the fragility and instability of drylands relative to forest ecasystems.Concuions:The findings from this study serve as important reference points to understand the ris of soil acidification in arid regions and its impacts on biodiversity-EMF relationships.
基金National Key Technology R&D Program of the Ministry of Science and Technology(2011BAD16B04,(2012BAD04B11)~~
文摘[Objective] The aim was to research the appropriate seeding quantities of double-season machine-transplanted rice in middle and low-yielding district of southern Jiangxi Province. [Method] The research set five different seeding quantities treatments, and compared with conventional seedling treatment, and the appropriate seeding quantities of double season machine-transplanted rice in middle and lowyielding district of southern Jiangxi Province was discussed. [Result] The yields were highest when the seeding quantity was 70 g per tray of early rice by mechanical transplanting and 60 g per tray of late rice. The yield of early rice by mechanical transplanting showed significantly positive correlation with the number of productive ear and the number of seed per ear, and late rice yield showed significant correlation with the number of productive ear by mechanical transplanting. It is key for improving high yields by guaranteeing the number of productive ear. [Conclusion] The issue of proper sowing quantity should be taken into consideration for double-cropping rice in the region, which is crucial for high yields.
文摘In this article, the names of 3 varieties of Monarda didyma L., which are considered to be introduced species, some indicators of the water regime in the climatic conditions of Uzbekistan: the amount of water in the leaves, water deficit, water storage capacity were studied in spring and summer, and seasonal changes were determined. According to these indicators of the water regime, the studied varieties belong to the labile water regime, high green mass (centner), seed yield (how many grams), resistance to diseases and pests have been determined, which shows that it is promising for introduction in the conditions of our republic. Therefore, it is recommended to breed these varieties in the foothills and hilly regions of Uzbekistan, where the amount of precipitation is more than 400 - 500 mm.
基金Supported by Yantai Science and Technology Development Program(2007155)~~
文摘Objective] The alm was to provide scientific references for determination of optimal N and P quantities of malze. [Method] The research conducted a test in field to expIore the effects of N and P fertiIizers on malze yield. [Result] Both of N and P fertiIizers have significant effects on malze yield. When malze yield reached the highest, the quantities of N fertiIizers and P fertiIizers were 530.56 and 105.44 kg/hm2, respectiveIy. [Conclusion] Malze yield keeps growing upon N or P fertiIizers to certaln extent, and excessive quantities of N and P fertiIizer wouId reduce malze yield.
文摘The presented work examines the mechanism and conditions of self-motion in bodies as systems of interacting elements. It is shown how the oscillation parameters of these elements determine the mode of motion of the system (body). In this case, the motion is considered as a consequence of symmetry breaking of forces in the systems themselves, and not as a reaction of individual elements to external influences. It is shown that such a violation takes place both in the gravitational field and when the system moves by inertia. Examples of the influence of changes in phase (φ) and frequency (f) parameters of the system elements on the velocity mode of its motion in space are considered. The identity of the causes of self-motion is revealed both in the case of gravitation and inertial motion.
文摘Widespread changes to forested watersheds affected by the mountain pine beetle (Dendroctonus ponderosae Hopkins) epidemic across western North America raised concerns about the effects of this climate-induced disturbance on drinking water and natural resources. Effective communication and knowledge exchange across scientists and stakeholders (i.e., drinking water managers) is essential for constructively responding to such landscape scale disturbances, providing improved adaptive capacity through knowledge sharing. An assessment of stakeholder knowledge levels, information needs, primary concerns, and suggested communication strategies were conducted via an online elicitation survey and World Science Café workshops. Knowledge levels, assessed via a survey of local water managers and experts, were relatively low with approximately half of the respondents reporting little to no knowledge of the effects of mountain pine beetle on drinking water quality and quantity, thereby indicating limited knowledge exchange between scientists and drinking water stakeholders. Increased accessibility and dissemination of research findings pertinent to the mountain pine beetle epidemic’s effects on drinking water quality and quantity is necessary for natural resource management. Recommendations for improved communication among scientists and drinking water stakeholders in particular and forest health in general include dispersal of non-academic research summaries, information exchange through existing media and community resources, demonstration projects, and information clearinghouses. This information provides a better understanding of the challenges, concerns, and first-hand experience of stakeholders of a landscape disturbance issue to apply this knowledge to enhance land management practice and how researchers on this overall project enhanced science communication efforts.
文摘The main purpose of this paper is to generalize the effect of two-phased demand and variable deterioration within the EOQ (Economic Order Quantity) framework. The rate of deterioration is a linear function of time. The two-phased demand function states the constant function for a certain period and the quadratic function of time for the rest part of the cycle time. No shortages as well as partial backlogging are allowed to occur. The mathematical expressions are derived for determining the optimal cycle time, order quantity and total cost function. An easy-to-use working procedure is provided to calculate the above quantities. A couple of numerical examples are cited to explain the theoretical results and sensitivity analysis of some selected examples is carried out.
基金The National Natural Science Foundation of China(No.70771026)
文摘The development and deployment of privary preserving supply chain quantity discount contract design can allow supply chain collaborations to take place without revealing any participant's data to others, reaping the benefits of collaborations wbile avoiding the drawbacks of privacy information disclosure. First, secure multi-party computation protocols are applied in the joint-ordering policy between a single supplier and a single retailer, the joint-ordering policy can be conducted without disclosing private cost information of any of the other supply chain partners. Secondly, secure multi-party computation protocols are applied in the privacy preserving supply chain quantity discount contract design between a single supplier and a single retailer. The information disclosure analyses of the algorithm show that: the optimal quantity discount of the jointordering policy can be conducted without disclosing private cost information of any of the other supply chain partners; the above protocol can be implemented without mediators; the privacy preserving quantity discount algorithm can be mutually verifiable and has solved the problem of asymmetric information.
文摘Urban peripheral green space (UPGS) plays more and more important rol e in sustaining urban physical and ecological environments. In this paper, a pre liminary classification of UPGS was presented for seven types and quantity index of UPGS was discussed tentatively. The quantity and layout problems in urban pe ripheral green space, and the several principles were mainly discussed in urban ventilation and sanitation, recreational opportunity and landscape ecological st ructure.