The seminal report ofα-diimine palladium and nickel catalysts in 1995 represented a major breakthrough in the preparation of functionalized polyolefin materials.Owing to the high abundance and low cost of nickel,nick...The seminal report ofα-diimine palladium and nickel catalysts in 1995 represented a major breakthrough in the preparation of functionalized polyolefin materials.Owing to the high abundance and low cost of nickel,nickel-based catalysts have great application prospects in the industrialization process of olefin coordination polymerization.In this work,various N-aryl substituents with different electronic effects were synthesized and introduced intoα-diimine ligands.The aspreparedα-diimine nickel catalysts showed high polymerization activity(0.9×10^(7)–3.0×10^(7)g·mol^(−1)·h^(−1))in ethylene polymerization,generating polyethylene products with adjustable molecular weights(Mn values:7.4×10^(4)–146.9×10^(4)g·mol^(−1))and branching densities(31/1000 C–68/1000 C).The resulting polyethylene products showed excellent mechanical properties,with high tensile strength(up to 25.0 MPa)and high strain at break values(up to 3890%).The copolymerization of ethylene and polar monomers can also be achieved by these nicekel complexes,ultimately preparing functionalized polyolefins.展开更多
A genetic model was proposed for simultaneously analyzing genetic effects of nuclear, cytoplasm, and nuclear-cytoplasmic interaction (NCI) as well as their genotype by environment (GE) interaction for quantitative...A genetic model was proposed for simultaneously analyzing genetic effects of nuclear, cytoplasm, and nuclear-cytoplasmic interaction (NCI) as well as their genotype by environment (GE) interaction for quantitative traits of diploid plants. In the model, the NCI effects were further partitioned into additive and dominance nuclear-cytoplasmic interaction components. Mixed linear model approaches were used for statistical analysis. On the basis of diallel cross designs, Monte Carlo simulations showed that the genetic model was robust for estimating variance components under several situations without specific effects. Random genetic effects were predicted by an adjusted unbiased prediction (AUP) method. Data on four quantitative traits (boll number, lint percentage, fiber length, and micronaire) in Upland cotton (Gossypium hirsutum L.) were analyzed as a worked example to show the effectiveness of the model.展开更多
Flotation reagents have a complex behaviour in the beneficiation of base minerals in clayey ores.Interaction effects of reagents on the efficiency of copper flotation for a highly clayey low-grade sulphide ore were in...Flotation reagents have a complex behaviour in the beneficiation of base minerals in clayey ores.Interaction effects of reagents on the efficiency of copper flotation for a highly clayey low-grade sulphide ore were investigated using a central composite design.Preliminary results showed that sodium-isopropyl-xanthate(SIPX)and O-isopropyl-N-ethyl-thionocarbamate(IPETC)were found to be the most efficient collectors in the presence of lime as the pH regulator.The effects of dosage of collectors(SIPX and IPETC)and the dosage of methyl-isobutyl-carbonyl(MIBC)as frother on the separation efficiency were evaluated at different pH levels.Based on the analysis of variance(ANOVA),the interaction effects of the collector−pH and collector−frother were significant for the separation efficiency.At the low level of collector dosage,increasing pH from 9 to 11 enhanced copper separation efficiency from 81%to 86%for IPETC and from 77%to 86%for SIPX.Results of ANOVA showed that the maximum copper separation efficiency(88.7%)was obtained at the dosages of 8.6 g/t SIPX,7 g/t IPETC and 20 g/t MIBC at pH 11.Finally,it was concluded that a mixture of SIPX and IPETC collectors was more suitable to treat highly clayey sulphide ores.展开更多
Effects of temperature, salinity and light intensity on growth rates of Gracilaria lichenoides and G. tenuistipitata var. liui Zhang et Xia were tested. Eight to ten levels of each factor were first tested separately....Effects of temperature, salinity and light intensity on growth rates of Gracilaria lichenoides and G. tenuistipitata var. liui Zhang et Xia were tested. Eight to ten levels of each factor were first tested separately. The best growth rate was obtained under the conditions of 32℃, 30 and 240 μmol/(m^2·s) for G. lichenoides, and 24℃, 20 and 200 μmol/(m^2·s) for G. tenuistipitata, respectively. Then a uniform design was used to evaluate the optimal combinations of the three factors. The best conditions for the highest daily specific growth rates (% increase in wet weight) are determined to be 31.30℃, 32.10, and 287.23 lamol/(m^2·s) for G. lichenoides (16.26%/d), and 25.38℃, 21.10, and 229.07 lamol/(m^2·s) for G tenuistipitata (14.83%/d), respectively.展开更多
Global change will lead to increases in regional precipitation and nitrogen(N) deposition in the semi-arid grasslands of northern China. We investigated the responses of vegetation carbon(C) pools to simulated pre...Global change will lead to increases in regional precipitation and nitrogen(N) deposition in the semi-arid grasslands of northern China. We investigated the responses of vegetation carbon(C) pools to simulated precipitation and N deposition increases through field experiments in a typical steppe in Inner Mongolia. The treatments included NH4NO3 addition at concentrations of 0(CK), 5(LN, low nitrogen), 10(middle nitrogen, MN), and 20(HN,high nitrogen)(g m^(-2)a^(-1)) with and without water. After three consecutive years of treatment, from 2010 to 2012,water addition did not significantly change the size of the total vegetation C pools, but it significantly decreased the ratio of root:shoot(R:S)(P = 0.05) relative to controls. By contrast, N addition significantly increased the total vegetation C pools. The C pools in the LN, MN and HN treatments increased by 22, 39 and 44 %, respectively. MN produced the largest effect among the N concentrations,although differences between N-added treatments were not significant(P ? 0.05). N addition significantly reduced the ratio of root:shoot(R:S)(P = 0.03). However, there were no significant interactive effects of water and N addition on the vegetation C pools.展开更多
Benggang erosion is caused by a special type of gully erosion in southern China that seriously endangers the local ecology and environment.In this study,typical Benggang collapsing-wall soils were used as the study ar...Benggang erosion is caused by a special type of gully erosion in southern China that seriously endangers the local ecology and environment.In this study,typical Benggang collapsing-wall soils were used as the study area to investigate the effects of different initial moisture contents and dicranopteris linearis root weight densities,as well as their interactions on disintegration in orthogonal test method.The results showed that the rate of soil disintegration decreased as a linear function of the initial moisture content.The soil disintegration rate tended to rise and then fall as the root weight density increased,reflecting an optimum root weight density of 0.75-1.00 g/100 cm3.The incorporation of dicranopteris linearis roots was most effective for soil consolidation in the shallow layers of soil.In addition,the disintegration rate of the collapsing-wall soils increases as the soil layer deepened.The dicranopteris linearis root system and initial moisture content had an interactive effect that was more pronounced in deeper soils.However,the combined effect of these processes was always dominated by the initial moisture content.Moderate initial soil moisture content(0.20-0.24 g/g)and the addition of a high root density in dicranopteris linearis(0.75-1.00 g/100 cm3)were the optimal combinations that reduced the disintegration rate.In conclusion,maintaining a suitable natural moisture content in collapsing-wall soils and taking measures that use plants to consolidate soil can effectively prevent and control the occurrence of Benggang erosion.The results of this study provided further insight into the factors that influence soil disintegration and offered a scientific basis for soil erosion management in the southern China.展开更多
To gain a better understanding of the anticancer effects of hydroxyapatite (HAP) nanoparticles in vivo and in vitro, the effects of the interaction of HAP nanoparticles with hepatoma cells were explored. HAP nanopar...To gain a better understanding of the anticancer effects of hydroxyapatite (HAP) nanoparticles in vivo and in vitro, the effects of the interaction of HAP nanoparticles with hepatoma cells were explored. HAP nanoparticles were prepared by homogeneous precipitation and characterized by laser particle analysis and transmission electron microscopy (TEM). HAP nanoparticles were observed to be uniformly distributed, with rod-like shapes and diameters in the range of 42.1-87.1 nm. Overnight attached, suspended, and proliferating Bel-7402 cells were incubated with HAP nanoparticles. Inverted microscopy observation revealed that HAP nanoparticles with a cell membrane showed good adsorption. TEM demonstrated that HAP nanoparticles were present on the surface of cells, continuously taken up by cells through endocytosis, and transported in vesicles close to the nucleus. Fluorescence microscopy showed that the concentrations of intracellular Ca2+ labeled with Fluo-3 calcium fluorescent probe were significantly enhanced. In addition, inverted microscopy observation revealed that suspended cells treated with HAP nanoparticles did not adhere to the culture bottle, resulting in cell death. After the overnight attached cells were treated with HAP nanoparticles for 96 h with increasing doses of HAP nanoparticles, inverted microscopy observation revealed that cell proliferation was slowed and ceU-ceU adhesion was weakened. Feulgen staining and image analysis indicated that the nuclear DNA content of the cells was markedly reduced, and argyrophilic nucleolar organizer region (AgNOR) staining and image analysis indicated that the number of AgNORs was significantly decreased. Therefore, hepatoma cells brought about the adsorption, uptake, transport and degradation of HAP nanoparticles. In addition, HAP nanoparticles affected hepatoma cells with regard to cell-cell adhesion, cell and extracellular matrix adhesion, and DNA and protein synthesis; thus inhibiting cell proliferation. This understanding of the effects of interaction between HAP nanoparticles and hepatoma cells is useful for further study of the anticancer mechanisms of HAP nanoparticles.展开更多
Taking the yield in the second group of Guizhou silage maize regional test in 2019 as data information, 8 experimental sites and 12 silage maize varieties as experimental objects, the interaction effect between gene a...Taking the yield in the second group of Guizhou silage maize regional test in 2019 as data information, 8 experimental sites and 12 silage maize varieties as experimental objects, the interaction effect between gene and environment was analyzed by using AMMI model. The results showed that the average fresh weight yield of each variety was 3 199.5~3 976.6 kg/667m^(2), among them, 5 varieties had an increase in the yield. Variety variation accounted for 10.51% of the total variation;experimental site variation accounted for 63.22% of the total variation;interaction effect variation between gene and environment accounted for 26.28% of the total variation;IPCA1 and IPCA2 variation accounted for 50.7% and 31.2% of the interaction variation, respectively;IPCA3 variation accounted for 7.25% of the interaction variation. g_4, g_8, g_9, g_10, g_11 and g_12 had better adaptability to e_1, e_2, e_6 and e_7;while g_1, g_2, g_3, g_5, g_6 and g_7 had better adaptability to e_3, e_4, e_5 and e_8. In consideration of yield, g_1(Huinongqing 2) and g_9(Xinyu 666) were silage maize varieties with high and stable yield;g_3(Hemuyu 905), g_8(Wuhuayu 3) and g_11(Liangdu 191) had general stability, and their yield was higher than that of the control;g_12(Jinduyu 999) had the worst stability and low yield.展开更多
This paper explores the effect of a liquid lithium curtain on fusion reactor plasma, such curtain is utilized as the first wall for the engineering outline design of the Fusion Experimental Breeder (FEB-E). The rela...This paper explores the effect of a liquid lithium curtain on fusion reactor plasma, such curtain is utilized as the first wall for the engineering outline design of the Fusion Experimental Breeder (FEB-E). The relationships between the surface temperature of a liquid lithium curtain and the effective plasma charge, fuel dilution and fusion power production have been derived. Results indicate that under normal operation, the evaporation of liquid lithium does not seriously affect the effective plasma charge, but effects on fuel dilution and fusion power are more sensitive. As an example, it has investigated the relationships between the liquid lithium curtain flow velocity and the rise of surface temperature based on operation scenario II of the FEB-E design with reversed shear configuration and high power density. Results show that even if the liquid lithium curtain flow velocity is as low as 0.5 m/s, the effects of evaporation from the liquid lithium curtain on plasma are negligible. In the present design, the sputtering of liquid lithium curtain and the particle removal effects of the divertor are not yet considered in detail. Further studies are in progress, and in this work implication of lithium erosion and divertor physics on fusion reactor operation are discussed.展开更多
It is known to all, the spilling of pipeline may cause serious problems, especially when the pipe conveying petroleum, natural gas or other toxic substance. There are countless accidents during past century. Once the ...It is known to all, the spilling of pipeline may cause serious problems, especially when the pipe conveying petroleum, natural gas or other toxic substance. There are countless accidents during past century. Once the spilling occurs, the vibration of the pipe would aggravate spill situation and even result in crack of the pipe. The consequence will be more severe when the fluid inside is compressible. To prevent the detriment of the spilling model is developed by assuming the leakages as orifices or nozzles and a 2-D vertical simply supported pipe is selected to analyze the phenomena of the oscillation. Combining these two models, the oscillation model for the pipe with leakage is set up and the spilling effect is analyzed by numerical method. The amplitude of the pipe oscillation and the normal stress enlarge as the internal velocity increased, while the shear stress changes very little.展开更多
Numerous researches have focused on the physical behavior of an elastic material in the vicinity of a single hole under the assumption that the interaction effects arising from the introduction of multiple holes remai...Numerous researches have focused on the physical behavior of an elastic material in the vicinity of a single hole under the assumption that the interaction effects arising from the introduction of multiple holes remain negligible if the holes are placed sufficiently far from each other.In an effort to understand hole interaction effects on heat conduction and thermal stress,we consider the case when two circular holes are embedded in an infinite elastic material and use complex variable methods together with numerical analysis to obtain solutions describing temperature and elastic fields in the vicinity of the two circular holes.The results indicate that the interaction effects on temperature distribution and stress strongly depend on the relative size of the two holes and the distance placed between them but not on the actual size of the holes.展开更多
We investigate the effects of pure Dzyaloshinskii Moriya (DM) interaction with magnetic field on entanglement in intrinsic decoherence, assuming that the system is initially in four Bell states |φ±〉 = (|00...We investigate the effects of pure Dzyaloshinskii Moriya (DM) interaction with magnetic field on entanglement in intrinsic decoherence, assuming that the system is initially in four Bell states |φ±〉 = (|00) ± |11〉)/√2 and |ψ±〉 = (|01) ±|10〉)/√2, respectively. It is found that if the system is initially in the state p1(0) = |φ+〉〈φ+1, the entanglement can obtain its maximum when the DM interaction vector D is in the plane of XOZ and magnetic field B = By with the infinite time t, moreover the entanglement is independent of By and t when By is perpendicular to D. In addition, we obtain similar results when the system is initially in the states p2(0) = |φ-〉〈φ-| or p3 (0) = |ψ+〉〈ψ+1. However, we find that if the system is initially in the state P4 (0) = |ψ-〉〈ψ-l, the entanglement can obtain its maximum for infinite t, when the DM vector is in the plane ofYOZ, XOZ, or XOY, with the magnetic field parallel to X, Y, or Z axis, respectively. Moreover, when the axial B is perpendicular to D for the initial state p4(O), the negativity oscillates with time t and reaches a stable value, the larger the value of B is, the greater the stable value is, and the shorter the oscillation time of the negativity is. Thus we can adjust the direction and value of the external magnetic field to obtain the maximal entanglement, and avoid the adverse effects of external environment in some initial state. This is feasible within the cun'ent experimental technology.展开更多
In a three-sphere system, the middle sphere is acted upon by two opposite depletion forces from the other two spheres. It is found that, in this system, the two depletion forces are coupled with each other and result ...In a three-sphere system, the middle sphere is acted upon by two opposite depletion forces from the other two spheres. It is found that, in this system, the two depletion forces are coupled with each other and result in a strengthened depletion force. So the difference of the depletion forces of the three-sphere system and its corresponding two two-sphere systems is introduced to describe the coupling effect of the depletion interactions. The numerical results obtained by Monte- Carlo simulations show that this coupling effect is affected by both the concentration of small spheres and the geometrical confinement. Meanwhile, it is also found that the mechanisms of the coupling effect and the effect on the depletion force from the ~eometry factor are the same.展开更多
In this paper,we consider the statistical inference problems for the fixed effect and variance component functions in the two-way classification random effects model with skewnormal errors.Firstly,the exact test stati...In this paper,we consider the statistical inference problems for the fixed effect and variance component functions in the two-way classification random effects model with skewnormal errors.Firstly,the exact test statistic for the fixed effect is constructed.Secondly,using the Bootstrap approach and generalized approach,the one-sided hypothesis testing and interval estimation problems for the single variance component,the sum and ratio of variance components are discussed respectively.Further,the Monte Carlo simulation results indicate that the exact test statistic performs well in the one-sided hypothesis testing problem for the fixed effect.And the Bootstrap approach is better than the generalized approach in the one-sided hypothesis testing problems for variance component functions in most cases.Finally,the above approaches are applied to the real data examples of the consumer price index and value-added index of three industries to verify their rationality and effectiveness.展开更多
The neuroimmune system of the brain:Early studies(1990’s)on the neurological consequences of human immunodeficiency virus-1(HIV-1)infection in the brain were instrumental in establishing that specific brain cell type...The neuroimmune system of the brain:Early studies(1990’s)on the neurological consequences of human immunodeficiency virus-1(HIV-1)infection in the brain were instrumental in establishing that specific brain cell types can function as an innate immune system within the brain and in that role influence cognitive function(Kaul et al.,2005).展开更多
Samples of undoped, and CuO, CaO, Al2O3 as well as V2O5 doped MnZn ferrite were prepared using standard ceramic method. The X-ray diffraction results for the base and doped ferrite samples show a single phase with spi...Samples of undoped, and CuO, CaO, Al2O3 as well as V2O5 doped MnZn ferrite were prepared using standard ceramic method. The X-ray diffraction results for the base and doped ferrite samples show a single phase with spinel cubic structure. The Mossbauer spectrum of the base sample indicates line broadening and overlapping due to relaxation of magnetic dipoles. The temperature dependence of DC-electrical conductivity has been discussed on the basis of electronic conduction (electron hopping) and ionic conduction mechanism.展开更多
Grain cooking and nutrient qualities are the most important components of rice (Oryza sativa L.) quality. A doubled haploid (DH) population from a cross between two japonica cultivars was used to examine the pheno...Grain cooking and nutrient qualities are the most important components of rice (Oryza sativa L.) quality. A doubled haploid (DH) population from a cross between two japonica cultivars was used to examine the phenotypic values and potential QTLs for the quality traits. The cooking and nutrient quality traits, including the amylose content (AC), the gel consistency (CJC), the gelatinization temperature (GT), and the protein content (PC), in rice grown under upland and lowland environments were evaluated. Significant differences for AC, GC, GT, and PC between upland and lowland environments were detected. The phenotypic values of all four traits were higher under upland environment than lowland environment. The value of PC under upland environment was significantly higher (by 37.9%) than that under lowland environment. This suggests that upland cultivation had large effect on both cooking and nutrient qualifies. A total of seven QTLs and twelve pairs of QTLs were detected to have significant additive and epistatic effects for the four traits. Significant Q x E interaction effects of two QTLs and two pairs of QTLs were also discovered. The general contribution of additive QTLs ranged from 1.91% to 19.77%. The Q × E interactions of QTLs QGt3 and QAc6 accounted for 8.99% and 47.86% of the phenotypic variation, respectively, whereas those of the 2 pairs of epistatic QTLs, QAc6-QAcllb and QAc8-QAc9, accounted for 32.54% and 11.82%, respectively. Five QTLs QGt6b, QGt8, QGt11, QGcl, and QPc2, which had relatively high general contribution and no Q x E interactions, were selected to facilitate the upland rice grain quality breeding.展开更多
The present article provides supplementary information of previous works of analytic models for predicting conductivity enhancements of carbon nanotube composites. The models, though fairly simple, are able to take ac...The present article provides supplementary information of previous works of analytic models for predicting conductivity enhancements of carbon nanotube composites. The models, though fairly simple, are able to take account of the effects of conductivity anisotropy, nonstraightness, and aspect ratio of the CNT additives on the conductivity enhancement of the composite and to give predictions agreeing well with existing experimental data. The omitted detailed derivation of this model is demonstrated in the present article with a more systematical analysis, which may help with further development in this direction. Furthermore, the effects of various orientation distributions of CNTs are reported here for the first time. The information may be useful in design or fabrication technology of CNT composites for better or specified conductivities.展开更多
We try to apply a constituent quark model (a variety chiral constituent quark model) and the resonating group approach for the multi-quark problems to compute the effective potential between the NN- in S-wave (the qua...We try to apply a constituent quark model (a variety chiral constituent quark model) and the resonating group approach for the multi-quark problems to compute the effective potential between the NN- in S-wave (the quarks in the nucleons N and N-, and the two nucleons relatively as well, are in S wave) so as to see the possibility if there may be a tight bound state of six quarks as indicated by a strong enhancement at threshold of pp- in J/ψ and B decays. The effective potential which we obtain in terms of the model and approach shows if the experimental enhancement is really caused by a tight S-wave bound state of six quarks, then the quantum number of the bound state is very likely to be I = 1, JPC= 0-+.展开更多
To improve multi-environmental trial(MET)analysis,a compound method—which combines factor analytic(FA)model with additive main effect and multiplicative interaction(AMMI)and genotype main effect plus genotype-by-envi...To improve multi-environmental trial(MET)analysis,a compound method—which combines factor analytic(FA)model with additive main effect and multiplicative interaction(AMMI)and genotype main effect plus genotype-by-environment interaction(GGE)biplot—was conducted in this study.The diameter at breast height of 36 open-pollinated(OP)families of Pinus taeda at six sites in South China was used as a raw dataset.The best linear unbiased prediction(BLUP)data of all individual trees in each site was obtained by fitting the spatial effects with the FA method from raw data.The raw data and BLUP data were analyzed and compared by using the AMMI and GGE biplot.BLUP results showed that the six sites were heterogeneous and spatial variation could be effectively fitted by spatial analysis with the FA method.AMMI analysis identified that two datasets had highly significant effects on the site,family,and their interactions,while BLUP data had a smaller residual error,but higher variation explaining ability and more credible stability than raw data.GGE biplot results revealed that raw data and BLUP data had different results in mega-environment delineation,test-environment evaluation,and genotype evaluation.In addition,BLUP data results were more reasonable due to the stronger analytical ability of the first two principal components.Our study suggests that the compound method combing the FA method with the AMMI and GGE biplot could improve the analysis result of MET data in Pinus teada as it was more reliable than direct AMMI and GGE biplot analysis on raw data.展开更多
基金supported by the National Key R&D Program of China(2021YFA1501700)Fundamental Research Funds for the Central Universities(WK9990000142).
文摘The seminal report ofα-diimine palladium and nickel catalysts in 1995 represented a major breakthrough in the preparation of functionalized polyolefin materials.Owing to the high abundance and low cost of nickel,nickel-based catalysts have great application prospects in the industrialization process of olefin coordination polymerization.In this work,various N-aryl substituents with different electronic effects were synthesized and introduced intoα-diimine ligands.The aspreparedα-diimine nickel catalysts showed high polymerization activity(0.9×10^(7)–3.0×10^(7)g·mol^(−1)·h^(−1))in ethylene polymerization,generating polyethylene products with adjustable molecular weights(Mn values:7.4×10^(4)–146.9×10^(4)g·mol^(−1))and branching densities(31/1000 C–68/1000 C).The resulting polyethylene products showed excellent mechanical properties,with high tensile strength(up to 25.0 MPa)and high strain at break values(up to 3890%).The copolymerization of ethylene and polar monomers can also be achieved by these nicekel complexes,ultimately preparing functionalized polyolefins.
基金This work was supported by Chinese National Programs for High Technology Research and Development(973 Program)(No.2004CB117306).
文摘A genetic model was proposed for simultaneously analyzing genetic effects of nuclear, cytoplasm, and nuclear-cytoplasmic interaction (NCI) as well as their genotype by environment (GE) interaction for quantitative traits of diploid plants. In the model, the NCI effects were further partitioned into additive and dominance nuclear-cytoplasmic interaction components. Mixed linear model approaches were used for statistical analysis. On the basis of diallel cross designs, Monte Carlo simulations showed that the genetic model was robust for estimating variance components under several situations without specific effects. Random genetic effects were predicted by an adjusted unbiased prediction (AUP) method. Data on four quantitative traits (boll number, lint percentage, fiber length, and micronaire) in Upland cotton (Gossypium hirsutum L.) were analyzed as a worked example to show the effectiveness of the model.
文摘Flotation reagents have a complex behaviour in the beneficiation of base minerals in clayey ores.Interaction effects of reagents on the efficiency of copper flotation for a highly clayey low-grade sulphide ore were investigated using a central composite design.Preliminary results showed that sodium-isopropyl-xanthate(SIPX)and O-isopropyl-N-ethyl-thionocarbamate(IPETC)were found to be the most efficient collectors in the presence of lime as the pH regulator.The effects of dosage of collectors(SIPX and IPETC)and the dosage of methyl-isobutyl-carbonyl(MIBC)as frother on the separation efficiency were evaluated at different pH levels.Based on the analysis of variance(ANOVA),the interaction effects of the collector−pH and collector−frother were significant for the separation efficiency.At the low level of collector dosage,increasing pH from 9 to 11 enhanced copper separation efficiency from 81%to 86%for IPETC and from 77%to 86%for SIPX.Results of ANOVA showed that the maximum copper separation efficiency(88.7%)was obtained at the dosages of 8.6 g/t SIPX,7 g/t IPETC and 20 g/t MIBC at pH 11.Finally,it was concluded that a mixture of SIPX and IPETC collectors was more suitable to treat highly clayey sulphide ores.
基金Supported by the 908 Special Program (908-02-04-07)the National Basic Research Program of China (973 Program, No. 2006CB400608)K. C. Wong Magna Fund in Ningbo University
文摘Effects of temperature, salinity and light intensity on growth rates of Gracilaria lichenoides and G. tenuistipitata var. liui Zhang et Xia were tested. Eight to ten levels of each factor were first tested separately. The best growth rate was obtained under the conditions of 32℃, 30 and 240 μmol/(m^2·s) for G. lichenoides, and 24℃, 20 and 200 μmol/(m^2·s) for G. tenuistipitata, respectively. Then a uniform design was used to evaluate the optimal combinations of the three factors. The best conditions for the highest daily specific growth rates (% increase in wet weight) are determined to be 31.30℃, 32.10, and 287.23 lamol/(m^2·s) for G. lichenoides (16.26%/d), and 25.38℃, 21.10, and 229.07 lamol/(m^2·s) for G tenuistipitata (14.83%/d), respectively.
基金supported by the National Natural Science Foundation of China(Nos.4137308441330528+1 种基金and41203054)the Special Fund for Agro-scientific Research in the Public Interest(No.201203012)
文摘Global change will lead to increases in regional precipitation and nitrogen(N) deposition in the semi-arid grasslands of northern China. We investigated the responses of vegetation carbon(C) pools to simulated precipitation and N deposition increases through field experiments in a typical steppe in Inner Mongolia. The treatments included NH4NO3 addition at concentrations of 0(CK), 5(LN, low nitrogen), 10(middle nitrogen, MN), and 20(HN,high nitrogen)(g m^(-2)a^(-1)) with and without water. After three consecutive years of treatment, from 2010 to 2012,water addition did not significantly change the size of the total vegetation C pools, but it significantly decreased the ratio of root:shoot(R:S)(P = 0.05) relative to controls. By contrast, N addition significantly increased the total vegetation C pools. The C pools in the LN, MN and HN treatments increased by 22, 39 and 44 %, respectively. MN produced the largest effect among the N concentrations,although differences between N-added treatments were not significant(P ? 0.05). N addition significantly reduced the ratio of root:shoot(R:S)(P = 0.03). However, there were no significant interactive effects of water and N addition on the vegetation C pools.
基金supported by the Special Projects of the Central Government Guiding Local Science and Technology Development in China(Guike.ZY21195022)the National Natural Science Foundation of China(No.42007055 and 42107350)。
文摘Benggang erosion is caused by a special type of gully erosion in southern China that seriously endangers the local ecology and environment.In this study,typical Benggang collapsing-wall soils were used as the study area to investigate the effects of different initial moisture contents and dicranopteris linearis root weight densities,as well as their interactions on disintegration in orthogonal test method.The results showed that the rate of soil disintegration decreased as a linear function of the initial moisture content.The soil disintegration rate tended to rise and then fall as the root weight density increased,reflecting an optimum root weight density of 0.75-1.00 g/100 cm3.The incorporation of dicranopteris linearis roots was most effective for soil consolidation in the shallow layers of soil.In addition,the disintegration rate of the collapsing-wall soils increases as the soil layer deepened.The dicranopteris linearis root system and initial moisture content had an interactive effect that was more pronounced in deeper soils.However,the combined effect of these processes was always dominated by the initial moisture content.Moderate initial soil moisture content(0.20-0.24 g/g)and the addition of a high root density in dicranopteris linearis(0.75-1.00 g/100 cm3)were the optimal combinations that reduced the disintegration rate.In conclusion,maintaining a suitable natural moisture content in collapsing-wall soils and taking measures that use plants to consolidate soil can effectively prevent and control the occurrence of Benggang erosion.The results of this study provided further insight into the factors that influence soil disintegration and offered a scientific basis for soil erosion management in the southern China.
基金Funded by the National Natural Science Foundation of China(Nos.81190133,51172171 and 51002109)the National Natural Science Foundation of Hubei Province((No.2013CFB354)the Excellent Youth Innovative Research Team Foundation and Talents Project of Hubei Polytechnic University(No.13xtz01)
文摘To gain a better understanding of the anticancer effects of hydroxyapatite (HAP) nanoparticles in vivo and in vitro, the effects of the interaction of HAP nanoparticles with hepatoma cells were explored. HAP nanoparticles were prepared by homogeneous precipitation and characterized by laser particle analysis and transmission electron microscopy (TEM). HAP nanoparticles were observed to be uniformly distributed, with rod-like shapes and diameters in the range of 42.1-87.1 nm. Overnight attached, suspended, and proliferating Bel-7402 cells were incubated with HAP nanoparticles. Inverted microscopy observation revealed that HAP nanoparticles with a cell membrane showed good adsorption. TEM demonstrated that HAP nanoparticles were present on the surface of cells, continuously taken up by cells through endocytosis, and transported in vesicles close to the nucleus. Fluorescence microscopy showed that the concentrations of intracellular Ca2+ labeled with Fluo-3 calcium fluorescent probe were significantly enhanced. In addition, inverted microscopy observation revealed that suspended cells treated with HAP nanoparticles did not adhere to the culture bottle, resulting in cell death. After the overnight attached cells were treated with HAP nanoparticles for 96 h with increasing doses of HAP nanoparticles, inverted microscopy observation revealed that cell proliferation was slowed and ceU-ceU adhesion was weakened. Feulgen staining and image analysis indicated that the nuclear DNA content of the cells was markedly reduced, and argyrophilic nucleolar organizer region (AgNOR) staining and image analysis indicated that the number of AgNORs was significantly decreased. Therefore, hepatoma cells brought about the adsorption, uptake, transport and degradation of HAP nanoparticles. In addition, HAP nanoparticles affected hepatoma cells with regard to cell-cell adhesion, cell and extracellular matrix adhesion, and DNA and protein synthesis; thus inhibiting cell proliferation. This understanding of the effects of interaction between HAP nanoparticles and hepatoma cells is useful for further study of the anticancer mechanisms of HAP nanoparticles.
基金Supported by National Modern Agricultural Industrial Technology System。
文摘Taking the yield in the second group of Guizhou silage maize regional test in 2019 as data information, 8 experimental sites and 12 silage maize varieties as experimental objects, the interaction effect between gene and environment was analyzed by using AMMI model. The results showed that the average fresh weight yield of each variety was 3 199.5~3 976.6 kg/667m^(2), among them, 5 varieties had an increase in the yield. Variety variation accounted for 10.51% of the total variation;experimental site variation accounted for 63.22% of the total variation;interaction effect variation between gene and environment accounted for 26.28% of the total variation;IPCA1 and IPCA2 variation accounted for 50.7% and 31.2% of the interaction variation, respectively;IPCA3 variation accounted for 7.25% of the interaction variation. g_4, g_8, g_9, g_10, g_11 and g_12 had better adaptability to e_1, e_2, e_6 and e_7;while g_1, g_2, g_3, g_5, g_6 and g_7 had better adaptability to e_3, e_4, e_5 and e_8. In consideration of yield, g_1(Huinongqing 2) and g_9(Xinyu 666) were silage maize varieties with high and stable yield;g_3(Hemuyu 905), g_8(Wuhuayu 3) and g_11(Liangdu 191) had general stability, and their yield was higher than that of the control;g_12(Jinduyu 999) had the worst stability and low yield.
基金Project supported by the National Natural Science Foundation of China (Grant No 10085001), and in part the U.S. Department of Energy (Contract No W-31-109-ENG-38).
文摘This paper explores the effect of a liquid lithium curtain on fusion reactor plasma, such curtain is utilized as the first wall for the engineering outline design of the Fusion Experimental Breeder (FEB-E). The relationships between the surface temperature of a liquid lithium curtain and the effective plasma charge, fuel dilution and fusion power production have been derived. Results indicate that under normal operation, the evaporation of liquid lithium does not seriously affect the effective plasma charge, but effects on fuel dilution and fusion power are more sensitive. As an example, it has investigated the relationships between the liquid lithium curtain flow velocity and the rise of surface temperature based on operation scenario II of the FEB-E design with reversed shear configuration and high power density. Results show that even if the liquid lithium curtain flow velocity is as low as 0.5 m/s, the effects of evaporation from the liquid lithium curtain on plasma are negligible. In the present design, the sputtering of liquid lithium curtain and the particle removal effects of the divertor are not yet considered in detail. Further studies are in progress, and in this work implication of lithium erosion and divertor physics on fusion reactor operation are discussed.
基金the support of Thousand Talents Programthe National Natural Science Foundation of China(51479114)special fund for Marine Renewable Energy Project(GHME2014ZC01)
文摘It is known to all, the spilling of pipeline may cause serious problems, especially when the pipe conveying petroleum, natural gas or other toxic substance. There are countless accidents during past century. Once the spilling occurs, the vibration of the pipe would aggravate spill situation and even result in crack of the pipe. The consequence will be more severe when the fluid inside is compressible. To prevent the detriment of the spilling model is developed by assuming the leakages as orifices or nozzles and a 2-D vertical simply supported pipe is selected to analyze the phenomena of the oscillation. Combining these two models, the oscillation model for the pipe with leakage is set up and the spilling effect is analyzed by numerical method. The amplitude of the pipe oscillation and the normal stress enlarge as the internal velocity increased, while the shear stress changes very little.
基金the National Natural Science Foundation of China(No.11902116)the China Postdoctoral Science Foundation(No.2020M671313)the Natural Sciences and Engineering Research Council of Canada(No.RGPIN 155112)。
文摘Numerous researches have focused on the physical behavior of an elastic material in the vicinity of a single hole under the assumption that the interaction effects arising from the introduction of multiple holes remain negligible if the holes are placed sufficiently far from each other.In an effort to understand hole interaction effects on heat conduction and thermal stress,we consider the case when two circular holes are embedded in an infinite elastic material and use complex variable methods together with numerical analysis to obtain solutions describing temperature and elastic fields in the vicinity of the two circular holes.The results indicate that the interaction effects on temperature distribution and stress strongly depend on the relative size of the two holes and the distance placed between them but not on the actual size of the holes.
基金Supported by the National Natural Science Foundation of China under Grant Nos 11204061,11374085,11104057,11274010 and 11204002the Anhui Provincial Natural Science Foundation under Grant No 1408085MA16+4 种基金the Anhui Provincial Candidates for Academic and Technical Leaders Foundation under Grant No 2015H052the Discipline Top-Notch Talents Foundationthe Excellent Young Talents Support Plan of Anhui Provincial Universitiesthe Specialized Research Fund for the Doctoral Program of Higher Education under Grant No 20113401110002the 211 Project of Anhui University,and the Personnel Department of Anhui Province
文摘We investigate the effects of pure Dzyaloshinskii Moriya (DM) interaction with magnetic field on entanglement in intrinsic decoherence, assuming that the system is initially in four Bell states |φ±〉 = (|00) ± |11〉)/√2 and |ψ±〉 = (|01) ±|10〉)/√2, respectively. It is found that if the system is initially in the state p1(0) = |φ+〉〈φ+1, the entanglement can obtain its maximum when the DM interaction vector D is in the plane of XOZ and magnetic field B = By with the infinite time t, moreover the entanglement is independent of By and t when By is perpendicular to D. In addition, we obtain similar results when the system is initially in the states p2(0) = |φ-〉〈φ-| or p3 (0) = |ψ+〉〈ψ+1. However, we find that if the system is initially in the state P4 (0) = |ψ-〉〈ψ-l, the entanglement can obtain its maximum for infinite t, when the DM vector is in the plane ofYOZ, XOZ, or XOY, with the magnetic field parallel to X, Y, or Z axis, respectively. Moreover, when the axial B is perpendicular to D for the initial state p4(O), the negativity oscillates with time t and reaches a stable value, the larger the value of B is, the greater the stable value is, and the shorter the oscillation time of the negativity is. Thus we can adjust the direction and value of the external magnetic field to obtain the maximal entanglement, and avoid the adverse effects of external environment in some initial state. This is feasible within the cun'ent experimental technology.
基金Project supported by the Scientific Research Fund of Hunan Provincial Education Department, China (Grant Nos. 08B028 and 10A075)the Natural Science Foundation of Hunan Province, China (Grant No. 08jj6043)
文摘In a three-sphere system, the middle sphere is acted upon by two opposite depletion forces from the other two spheres. It is found that, in this system, the two depletion forces are coupled with each other and result in a strengthened depletion force. So the difference of the depletion forces of the three-sphere system and its corresponding two two-sphere systems is introduced to describe the coupling effect of the depletion interactions. The numerical results obtained by Monte- Carlo simulations show that this coupling effect is affected by both the concentration of small spheres and the geometrical confinement. Meanwhile, it is also found that the mechanisms of the coupling effect and the effect on the depletion force from the ~eometry factor are the same.
基金supported by National Social Science Foundation of China(21BTJ068)。
文摘In this paper,we consider the statistical inference problems for the fixed effect and variance component functions in the two-way classification random effects model with skewnormal errors.Firstly,the exact test statistic for the fixed effect is constructed.Secondly,using the Bootstrap approach and generalized approach,the one-sided hypothesis testing and interval estimation problems for the single variance component,the sum and ratio of variance components are discussed respectively.Further,the Monte Carlo simulation results indicate that the exact test statistic performs well in the one-sided hypothesis testing problem for the fixed effect.And the Bootstrap approach is better than the generalized approach in the one-sided hypothesis testing problems for variance component functions in most cases.Finally,the above approaches are applied to the real data examples of the consumer price index and value-added index of three industries to verify their rationality and effectiveness.
基金supported by National Institutes of Health Grant AA024484(to DLG)。
文摘The neuroimmune system of the brain:Early studies(1990’s)on the neurological consequences of human immunodeficiency virus-1(HIV-1)infection in the brain were instrumental in establishing that specific brain cell types can function as an innate immune system within the brain and in that role influence cognitive function(Kaul et al.,2005).
文摘Samples of undoped, and CuO, CaO, Al2O3 as well as V2O5 doped MnZn ferrite were prepared using standard ceramic method. The X-ray diffraction results for the base and doped ferrite samples show a single phase with spinel cubic structure. The Mossbauer spectrum of the base sample indicates line broadening and overlapping due to relaxation of magnetic dipoles. The temperature dependence of DC-electrical conductivity has been discussed on the basis of electronic conduction (electron hopping) and ionic conduction mechanism.
基金This work was supported by the State Key Basic Research and Development Plan of China (973)the Hi-Tech Research and De-velopment Program of China (863) National Natural Science Foundation of China.
文摘Grain cooking and nutrient qualities are the most important components of rice (Oryza sativa L.) quality. A doubled haploid (DH) population from a cross between two japonica cultivars was used to examine the phenotypic values and potential QTLs for the quality traits. The cooking and nutrient quality traits, including the amylose content (AC), the gel consistency (CJC), the gelatinization temperature (GT), and the protein content (PC), in rice grown under upland and lowland environments were evaluated. Significant differences for AC, GC, GT, and PC between upland and lowland environments were detected. The phenotypic values of all four traits were higher under upland environment than lowland environment. The value of PC under upland environment was significantly higher (by 37.9%) than that under lowland environment. This suggests that upland cultivation had large effect on both cooking and nutrient qualifies. A total of seven QTLs and twelve pairs of QTLs were detected to have significant additive and epistatic effects for the four traits. Significant Q x E interaction effects of two QTLs and two pairs of QTLs were also discovered. The general contribution of additive QTLs ranged from 1.91% to 19.77%. The Q × E interactions of QTLs QGt3 and QAc6 accounted for 8.99% and 47.86% of the phenotypic variation, respectively, whereas those of the 2 pairs of epistatic QTLs, QAc6-QAcllb and QAc8-QAc9, accounted for 32.54% and 11.82%, respectively. Five QTLs QGt6b, QGt8, QGt11, QGcl, and QPc2, which had relatively high general contribution and no Q x E interactions, were selected to facilitate the upland rice grain quality breeding.
文摘The present article provides supplementary information of previous works of analytic models for predicting conductivity enhancements of carbon nanotube composites. The models, though fairly simple, are able to take account of the effects of conductivity anisotropy, nonstraightness, and aspect ratio of the CNT additives on the conductivity enhancement of the composite and to give predictions agreeing well with existing experimental data. The omitted detailed derivation of this model is demonstrated in the present article with a more systematical analysis, which may help with further development in this direction. Furthermore, the effects of various orientation distributions of CNTs are reported here for the first time. The information may be useful in design or fabrication technology of CNT composites for better or specified conductivities.
文摘We try to apply a constituent quark model (a variety chiral constituent quark model) and the resonating group approach for the multi-quark problems to compute the effective potential between the NN- in S-wave (the quarks in the nucleons N and N-, and the two nucleons relatively as well, are in S wave) so as to see the possibility if there may be a tight bound state of six quarks as indicated by a strong enhancement at threshold of pp- in J/ψ and B decays. The effective potential which we obtain in terms of the model and approach shows if the experimental enhancement is really caused by a tight S-wave bound state of six quarks, then the quantum number of the bound state is very likely to be I = 1, JPC= 0-+.
基金supported by State Key Laboratory of Tree Genetics and Breeding(Northeast Forestry University)(K2013204)co-financed with NSFC project(31470673)Guangdong Science and Technology Planning Project(2016B070701008)
文摘To improve multi-environmental trial(MET)analysis,a compound method—which combines factor analytic(FA)model with additive main effect and multiplicative interaction(AMMI)and genotype main effect plus genotype-by-environment interaction(GGE)biplot—was conducted in this study.The diameter at breast height of 36 open-pollinated(OP)families of Pinus taeda at six sites in South China was used as a raw dataset.The best linear unbiased prediction(BLUP)data of all individual trees in each site was obtained by fitting the spatial effects with the FA method from raw data.The raw data and BLUP data were analyzed and compared by using the AMMI and GGE biplot.BLUP results showed that the six sites were heterogeneous and spatial variation could be effectively fitted by spatial analysis with the FA method.AMMI analysis identified that two datasets had highly significant effects on the site,family,and their interactions,while BLUP data had a smaller residual error,but higher variation explaining ability and more credible stability than raw data.GGE biplot results revealed that raw data and BLUP data had different results in mega-environment delineation,test-environment evaluation,and genotype evaluation.In addition,BLUP data results were more reasonable due to the stronger analytical ability of the first two principal components.Our study suggests that the compound method combing the FA method with the AMMI and GGE biplot could improve the analysis result of MET data in Pinus teada as it was more reliable than direct AMMI and GGE biplot analysis on raw data.