Fusarium graminearum(F.graminearum)is a severe phytopathogen threatening agriculture production and food security.Paeonol,serves as a plant-derived natural component,is a promising antifungal agent.At a concentration ...Fusarium graminearum(F.graminearum)is a severe phytopathogen threatening agriculture production and food security.Paeonol,serves as a plant-derived natural component,is a promising antifungal agent.At a concentration of 0.3125 mg/mL,paeonol was adequate to fully inhibit the growth of F.graminearum mycelia within 3 days.Fourier-Transform Infrared Spectroscopy(FT-IR)analysis showed that paeonol had no impact on the outer surface of F.graminearum cell walls.While propidium iodide staining,extracellular conductivity,and pH value measurements demonstrated that paeonol disrupted the cell membrane.Furthermore,lipid oxidation and osmotic stress responses were observed in F.graminearum treated with paeonol,resulting in a 47.23%rise in malondialdehyde(MDA)levels and a 515.43%increase in glycerol levels.Moreover,on the 7th day after exposure to paeonol treatment,the deoxynivalenol(DON)level was significantly reduced,measuring only onefifth of that in the control group.Finally,paeonol was shown to inhibit F.graminearum on wheat grains and steamed bread slices.These results,for the first time,revealed the inhibitory mode of action of paeonol against F.graminearum as reflected by disruption of cell membrane integrity,induction of lipid oxidation and osmotic pressure,as well as DON biosynthesis.Furthermore,this study provided scientific evidence for the potential applications of paeonol in agriculture and food industry.展开更多
The dynamic mechanical response and deformation mechanism of magnesium-yttrium alloy at high strain rate were investigated using split-Hopkinson pressure bar(SHPB)impact,and the microstructure evolution and crack form...The dynamic mechanical response and deformation mechanism of magnesium-yttrium alloy at high strain rate were investigated using split-Hopkinson pressure bar(SHPB)impact,and the microstructure evolution and crack formation mechanism were revealed.The yield strength and work hardening rate increase significantly with increasing impact strain rate.Deformation twinning and non-basal dislocation slip are the primary deformation mechanisms during testing.Contrary to crack initiation mechanism facilitated by adiabatic shear bands,we find that high-density co-axial nanocrystalline grains form near cracks,which leads to local softening and promotes crack initiation and rapid propagation.Most grains have similar<1^(-)21^(-)0>orientations,with unique misorientation of 24°,32°,62°,78°and 90°between adjacent grains,suggesting that these grains are primarily formed by interface transformation,which exhibits distinct differences from recrystallized grains.Our results shed light upon the dynamic mechanical response and crack formation mechanism in magnesium alloys under impact deformation.展开更多
Bioremediation has gained significant attention due to its potential to remove azo dyes.However,the challenges microor-ganisms face in surviving when azo dyes are the sole carbon source limit its widespread applicatio...Bioremediation has gained significant attention due to its potential to remove azo dyes.However,the challenges microor-ganisms face in surviving when azo dyes are the sole carbon source limit its widespread application.This study aimed to improve the biodegradation of azo dyes by utilizing Baijiu distiller’s grains leachate(BDGL)as a co-substrate.The experimental results demon-strated that BDGL significantly enhanced Providencia rettgeri’s ability to degrade the model pollutant Acid Black 210(AB210),achieving a decolorization efficiency of 94.5%.This may be attributed to the nutrient-rich composition of BDGL,which includes ethanol and protein,providing a favorable substrate for bacterial growth and activity.The higher biomass and increased activities of azoreductase and quinone oxidoreductase in the BDGL group further supported these findings.Additionally,this method demonstra-ted broad-spectrum degradation of azo dyes(Direct Red 5B,Acid Red 73,and Congo Red)with different structures,highlighting its potential applicability.Metabolite assays combined with transcriptomics analyses revealed that the expression of functional genes re-lated to redox reactions,azo bond cleavage,and hydrolysis increased under the co-metabolic conditions of BDGL,resulting in stronger reducing power that further mineralized the dye into smaller metabolites.Our study offers a practical strategy for the simulta-neous treatment of dye-containing wastewater and Baijiu distiller’s grains,with significant environmental and industrial applications.展开更多
Rice is a well-recognized accumulator of arsenic(As),which poses a threat to food security and human health.Different rice varieties vary widely in their As accumulation and tolerance,yet the underlying genetic basis ...Rice is a well-recognized accumulator of arsenic(As),which poses a threat to food security and human health.Different rice varieties vary widely in their As accumulation and tolerance,yet the underlying genetic basis remains unknown.In this study,we isolated a rice mutant hag1,which displayed high accumulation of As in rice grains and increased sensitivity to As toxicity.Using genetic investigation,we identified the ATP-binding cassette(ABC)transporter OsABCC1,involved in sequestering As in vacuoles,as the causal gene responsible for As allocation and tolerance in rice.Detailed physiological analysis revealed that As stress caused more severe oxidative damage in hag1 compared with the wild type(WT).The hag1 mutant displayed different accumulation patterns depending on the levels of As stress.We discovered that under low As concentration,hag1 synthesized more thiol compounds and exhibited lower As translocation than the WT;however,at high As levels,hag1 produced fewer thiol compounds and increased As transfer factor.Transcriptome analysis of the node nearest to the panicles revealed that OsABCC1 was down-regulated in hag1,resulting in increased As translocation and accumulation in rice grains.Additionally,natural variations in the promoter of OsABCC1 may confer differential gene expression and distinct As accumulations in grains between japonica and indica rice varieties,providing insights for breeding low-As rice varieties.展开更多
Hot compression experiments were conducted under conditions of deformation temperatures ranging from 950 to 1150℃,strain rates of 0.001-10 s^(-1),and deformation degrees ranging from 20%to 80%.The hot deformation beh...Hot compression experiments were conducted under conditions of deformation temperatures ranging from 950 to 1150℃,strain rates of 0.001-10 s^(-1),and deformation degrees ranging from 20%to 80%.The hot deformation behavior and microstructure evolution of millimeter-grade coarse grains(MCGs)in the as-cast Ti-6Cr-5Mo-5V-4Al(Ti-6554)alloy were studied,and a hot processing map was established.Under compression along the rolling direction(RD),continuous dynamic recrystallization(CDRX)ensues due to the progressive rotation of subgrains within the MCGs.Along the transverse direction(TD),discontinuous dynamic recrystallization(DDRX)resulting from grain boundary bulging or bridging,occurs on the boundaries of the MCGs.With decreasing strain rate,increasing temperature,and higher deformation degree,dynamic recrystallization becomes more pronounced,resulting in a reduction in the original average grain size.The optimal processing parameters fall within a temperature range of 1050-1150℃,a strain rate of 0.01 s^(-1),and a deformation degree between 40%and 60%.展开更多
In this study,two wheat-derived cadmium(Cd)-immobilizing endophytic Pseudomonas paralactis M14 and Priestia megaterium R27 were evaluated for their effects on wheat tissue Cd uptake under hydroponic conditions.Then,th...In this study,two wheat-derived cadmium(Cd)-immobilizing endophytic Pseudomonas paralactis M14 and Priestia megaterium R27 were evaluated for their effects on wheat tissue Cd uptake under hydroponic conditions.Then,the impacts of the biochar(BC),M14+R27(MR),and BC+MR treatments on wheat Cd uptake and the mechanisms involved were investigated at the jointing,heading,and mature stages of wheat plants under field-plot conditions.A hydroponic experiment showed that the MR treatment significantly decreased the above-ground tissue Cd content compared with theM14 or R27 treatment.The BC+MRtreatment reduced the grain Cd content by 51.5%-67.7%and Cd translocation factor at the mature stage of wheat plants and increased the organic matter-bound Cd content by 31%-75%in the rhizosphere soils compared with the BC or MR treatment.Compared with the BC or MR treatment,the relative abundances of the biomarkers associated with Gemmatimonas,Altererythrobacter,Gammaproteobacteria,Xanthomonadaceae,Phenylobacterium,and Nocardioides in the BC+MR-treated rhizosphere microbiome decreased and negatively correlated with the organic matter-bound Cd contents.In the BC+MR-treated root interior microbiome,the relative abundance of the biomarker belonging to Exiguobacterium increased and negatively correlated with the Cd translocation factor,while the relative abundance of the biomarker belonging to Pseudonocardiaceae decreased and positively correlated with the Cd translocation factor.Our findings suggested that the BC+MR treatment reduced Cd availability and Cd transfer through affecting the abundances of these specific biomarkers in the rhizosphere soil and root interior microbiomes,leading to decreased wheat grain Cd uptake in the contaminated soil.展开更多
[Objective] The aim is to study the construction of vectors expressing foreign protein in potato starch grains specifically, and provide some reference for solving industrialized core problem of high cost and low expr...[Objective] The aim is to study the construction of vectors expressing foreign protein in potato starch grains specifically, and provide some reference for solving industrialized core problem of high cost and low expression level of foreign protein. [Method] By using molecular biological techniques of RT-PCR and nested PCR, plant expression vector for the foreign protein locating in the potato starch grains was constructed. [ Result] Coding sequence （ GC20 ） of potato starch grains that was located and expressed by GBSSI promoter was cloned. Plant expression vector was screened out through connection, transformation and enzyme digestion identification. [ Conclusion] This result laid a foundation for further screening the foreign protein on the potato starch grains.展开更多
The random distribution problem of dendrite preferred growth direction was settled by random grid method.This method was used to study the influence of forced laminar flow effect on multiple grains during solidificati...The random distribution problem of dendrite preferred growth direction was settled by random grid method.This method was used to study the influence of forced laminar flow effect on multiple grains during solidification.Taking high pure succinonitrile （SCN） undercooled melt as an example,the forced laminar flow effect on multiple grains was studied by phase-field model of single grain which coupled with flow equations at non-isothermal condition.The simulation results show that the random grid method can reasonably settle the problem of random distribution and is more effective.When the solid fraction is relatively low,melt particles flow around the downstream side of dendrite,and the flow velocity between two dendrite arms becomes high.At the stage of solidification time less than 1800Δt,every dendrite grows freely;the upstream dendrites are stronger than the downstream ones.The higher the melt flow rate,the higher the solid fraction.However,when the solid fraction is relatively high,the dendrite arm intertwins and only a little residual melt which is not encapsulated can flow;the solid fraction will gradually tend to equal to solid fraction of melt without flow.展开更多
Compared with Cu/Al_(2)O_(3)composites,high-strength Cu/Al_(2)O_(3)composites usually exhibit obviously deteriorated electrical conductivity.A chemical and mechanical alloying-based strategy was adopted to fabricate u...Compared with Cu/Al_(2)O_(3)composites,high-strength Cu/Al_(2)O_(3)composites usually exhibit obviously deteriorated electrical conductivity.A chemical and mechanical alloying-based strategy was adopted to fabricate ultrafine composite powders with lowcontent reinforcement and constructed a combined structure of Cu ultrafine powders covered with in-situ Al_(2)O_(3)nanoparticles.After consolidation at a relatively lower sintering temperature of 550℃,high-volume-fraction ultrafine grains were introduced into the Cu/Al_(2)O_(3)composite,and many in-situ Al_(2)O_(3)nanoparticles with an average size of 11.7±7.5 nm were dispersed homogeneously in the Cu grain.Results show that the composite demonstrates an excellent balance of high tensile strength(654±1 MPa)and high electrical conductivity(84.5±0.1%IACS),which is ascribed to the synergistic strengthening effect of ultrafine grains,dislocations,and in-situ Al_(2)O_(3)nanoparticles.This approach,which utilizes ultrafine composite powder with low-content reinforcement as a precursor and employs low-temperature and high-pressure sintering subsequently,may hold promising potential for large-scale industrial production of high-performance oxide dispersion strengthened alloys.展开更多
Inferior grains exhibit delayed developmental processes and reduced metabolic activities compared to superior grains,leading to unstable rice yield and quality.While significant advancements have been achieved in eluc...Inferior grains exhibit delayed developmental processes and reduced metabolic activities compared to superior grains,leading to unstable rice yield and quality.While significant advancements have been achieved in elucidating the physiology of endosperm filling in inferior grains,the role of the embryo remains underexplored and warrants comprehensive investigation.Two Wuyujing 3 mutants,DW024(relatively synchronous;syn-DW024)and DW179(significantly asynchronous;asyn-DW179),with different grain-filling patterns were used in this study.Samples of superior and inferior grains were collected at intervals from 5 to 60 d after fertilization and subsequently dissected into subsamples of the embryo and endosperm.Histochemical staining,biochemical analysis,and RNA sequencing(RNA-seq)were combined to systematically compare developmental and physiological traits between superior and inferior grains.Combining hierarchical clustering of mRNA datasets revealed three developmental phases of the endosperm and embryo:morphogenesis,endosperm filling/embryo enlargement,and maturation.In both syn-DW024 and asyn-DW179,the duration of the endosperm/embryo morphogenesis phase was identical in superior and inferior grains.The inferior grains of asyn-DW179 exhibited a 10-day prolongation in the endosperm filling phase and a 20-day extension in the embryo enlargement phase compared to the superior grains.The endosperm of inferior grains exhibited higher contents of sugars and free amino acids,along with slower accumulation of storage compounds,which was associated with the down-regulation of genes for starch synthesis and ABA signaling.In addition,transporters for nutrient exchanges between endosperm and embryo were down-regulated,suggesting a potential role of the embryo in adjusting the endosperm filling process.Collectively,our results reveal that the prolonged phases of endosperm filling and embryo enlargement may underlie the impaired development of inferior grains,offering a new perspective for breeding or cultivating rice with uniform grain quality.展开更多
Background The diverse types and processing methods of grains intricately influence the sites and digestibility of starch digestion,thereby impacting energy utilization.This study aimed to explore the impact of grain ...Background The diverse types and processing methods of grains intricately influence the sites and digestibility of starch digestion,thereby impacting energy utilization.This study aimed to explore the impact of grain variety and processing methods on the net energy(NE)in dairy goats,analyzing these effects at the level of nutrient digestion and metabolism.Methods Eighteen castrated Guanzhong dairy goats(44.25±3.59 kg BW)were randomly divided into 3 groups,each consisting of 6 replicates.The substitution method was employed to determine the NE values of the dry-rolled corn(DRC),dry-rolled wheat(DRW)or steam-flaked corn(SFC,360 g/L).Briefly,two phases were performed.Throughout the basal phase,all goats were fed the same basal diet.In the substitution phase,30%of the basal diet was replaced with DRC,DRW and SFC,respectively.Results In this study,the NE values of the DRC,DRW and SFC were 7.65,7.54 and 7.44 MJ/kg DM,respectively.Compared to the DRC group,the DRW group showed increased digestibility of starch and crude protein(CP).Similarly,the SFC group exhibited increased organic matter(OM)and starch digestibility and a trend towards higher dry matter(DM)digestibility,reduced fecal OM and starch content.Additionally,fecal volatile fatty acid(VFA)concentrations decreased in goats fed SFC.Correspondingly,digestible energy(DE)in the DRW and SFC groups tended to be higher than in the DRC group.DRW increased total VFA concentration compared to DRC,while SFC increased the proportion of propionate and decreased the acetate-to-propionate ratio in the rumen.Both the DRW and SFC diets elevated serum glucose levels.Furthermore,heat increment(HI)and gaseous energy(Gas E)related to fermentation were significantly higher in the DRW and SFC groups compared to the DRC group.Conclusion Our findings indicated that DRW and SFC increased rumen starch fermentation in goats,thereby improving total tract starch digestion and DE.However,DRW and SFC failed to improve NE value due to increased heat and gas energy production from fermentation.Therefore,excessively refined grains processing in the diet of dairy goats does not effectively improve energy efficiency.展开更多
The rapid development of magnetic materials provides the possibility for the application of permanent magnet stirring(PMS).Numerical and experimental investigations were employed with respect to the solidification pro...The rapid development of magnetic materials provides the possibility for the application of permanent magnet stirring(PMS).Numerical and experimental investigations were employed with respect to the solidification process of the Al—2Sc alloy controlled by a novel PMS using NdFeB permanent magnets under various rotation speeds(0,50,100 and 150 r/min).The simulated results reveal that the maximum electromagnetic force increases proportionally from 4.14 to 12.39 kN/m^(3)and the maximum tangential velocity increases from 0.13 to 0.36 m/s when the rotation speed of PMS enhances from 50 to 150 r/min in the ingot melt.Besides,the experimental results demonstrate that PMS can achieve a uniform distribution of blocky Al_(3)Sc precipitated phase in the longitudinal direction under the impact of a forced fluid flow.Moreover,increasing rotation speed of PMS is beneficial to refining aluminum grain size significantly and decreasing the texture intensity in the alloy.In addition,the Brinell hardness of Al-2Sc alloy is increased by 33%to 27.8 HB and the tensile strength is enhanced by 34%-128.2 MPa,due to the improved distribution of the strengthening Al_(3)SC phase and the grain refinement of Al matrix under the impact of PMS.This work provides an effective application of NdFeB permanent magnets in the metal cast field.展开更多
Copper calcium titanate(CaCu_(3)Ti_(4)O_(12),CCTO)ceramics with colossal permittivity have gained widespread concern because of their potential application in modern electronic devices with miniaturization and integra...Copper calcium titanate(CaCu_(3)Ti_(4)O_(12),CCTO)ceramics with colossal permittivity have gained widespread concern because of their potential application in modern electronic devices with miniaturization and integration.However,the extent of grain and grain boundary contribution to the colossal permittivity of CCTO-based ceramics based on the internal barrier layer capacitor(IBLC)model is still in debate.This affects their electrical performance optimization and real-world applications.In this study,a series of novel lead-free colossal permittivity ceramic s,xLiCuNb_(3)O_(9-)(1-x)CaCu_(3)Ti_(4)O_(12)(LCNOCCTO),were designed and prepared using a solid-phase reaction approach.The colossal permittivity response mechanism of LCNO-CCTO ceramics was further explored by performing the complex impedance spectrum and analyzing the activation energy from the grain and grain boundary contribution viewpoint.As a result,the LCNO-CCTO ceramics present the cubic perovskite structure with the space groups of■.All the LCNOCCTO ceramics exhibit the significantly enhanced colossal permittivity(10^(5))response,and the ceramic with x=0.15 shows the highest permittivity of about 4.64×10^(5)(20 Hz,room temperature)accompanied by a lower grain resistance of 9.61Ωand larger grain activation energy of 0.21 eV.The enhanced colossal permittivity response is primarily attributed to the great electrical response inside grains of LCNO-CCTO ceramics,resulting from a smaller grain resistance.Also importantly,the high-frequency dielectric relaxation characteristics are improved by incorporating the LCNO into CCTO ceramics as an ion form.Accordingly,the LCNO-CCTO ceramics show a suppressed high-frequency dielectric loss.These results can provide a thorough knowledge and useful optimization strategy for developing high-performance colossal permittivity materials.展开更多
[Objective] The aim was to study characters of pollen grains of tetraploid lines and diploid control line of Chrysanthemum cinerariifolium (Trev.) Vis.,morphological characters,fertility of pollen grain and germinatio...[Objective] The aim was to study characters of pollen grains of tetraploid lines and diploid control line of Chrysanthemum cinerariifolium (Trev.) Vis.,morphological characters,fertility of pollen grain and germination percentage of seeds. [Method] Pollen grains were prepared by sulphuric acid-acetyl oxide decomposition method. The lengths of polar axis and equatorial axis of pollen grains were determined with general optical microscope. The morphology of pollen grains was observed with SEM (scanning electron microscope) and the typical visual fields of 2 500× (or 2 000×),7 000× were taken pictures. [Result] Comparing with the diploid control line,the pollen grains of five tetraploid lines which were tested were different from the diploid line in morphology,sculpture,etc.. 4 of the 5 tested samples were significant larger than the diploid line in size and one was similar to the diploid line. [Conclusion] This research provided references for breeding tetraploid improved varieties of Chrysanthemum cinerariifolium (Trev.) Vis. with good fertility and high germination percentage.展开更多
Cytochemical and ultrastructural studies indicated that compound spherical bodies observed near the sieve plate in the sieve tube members during the period of cambial dormancy in the shoots of Eucommia ulmoides O...Cytochemical and ultrastructural studies indicated that compound spherical bodies observed near the sieve plate in the sieve tube members during the period of cambial dormancy in the shoots of Eucommia ulmoides Oliv. were polysaccharide bodies different from the polysaccharide grains in other parenchyma cells in shoots, and were similar to cell walls in their staining properties. The compound spherical bodies occurred in the sieve elements during the period of cambial rest and disappeared in the sieve elements during the period of cambial quiescence and activity.展开更多
In cross sections by microscopic studies have examined the features of the shell thickness grains, cells, aleuronic layer and endosperm in the species T. dicoccum Schuebl., sorts Mironovskaya-808 and their interspecif...In cross sections by microscopic studies have examined the features of the shell thickness grains, cells, aleuronic layer and endosperm in the species T. dicoccum Schuebl., sorts Mironovskaya-808 and their interspecific hybrids F9 （alloplasmatic lines）. The result of studies showed the specific and varietal differences, and differences in hybrid plants on linear parameters size grains, the degree of specificity of the shells grains of wheat and identified species and varietal differences as well as differences among hybrids in the linear dimensions of the cells of the aleuronic layer. It is shown that among the studied forms of wheat allocated species T. dicoccum Shuebl. and the lines D-N-05, D-F-05 and D-40-05-KhNA with relatively large grains, a well-developed endosperm, most of thin shells and large grain aleurone layer cells. They are of most interest for further breeding research in terms of nutritional value.展开更多
In authors’ previous work [Mater. Charact. 141 (2018) 212-222]. it was found that the heterogeneous deformed microstructures can be replaced by the relatively homogeneous recrystallized grains through an annealing tr...In authors’ previous work [Mater. Charact. 141 (2018) 212-222]. it was found that the heterogeneous deformed microstructures can be replaced by the relatively homogeneous recrystallized grains through an annealing treatment. However, there are still some relatively large recrystallized grains. To find the reasons for the formation of large grains, some new annealing treatment tests were done, and the cellular automation (CA) simulations were carried out in the present work. The experimental results showed that the microstructural evolution during annealing treatment is significantly affected by the content of S phase. So. the effects of δ phase on the nucleation and growth of grains are carefully considered in the CA model to accurately simulate the microstructural evolution behavior. By the CA simulation, it is found that the dislocation density rapidly decreases due to the nucleation of static recrystallization (SRX) and the growth of dynamc recrystallization (DRX) nuclei at the early stage of annealing. The high initial dislocation density provide the high velocity for the growth of DRX nuclei, which is responsible for the formation of coarse grains, However, the growth rate of SRX nuclei is relatively small due to the low dislocation density and pinning effects of δ phase.展开更多
The formation of fine,non-dendritic equiaxed grains throughout a casting without the addition of refiners(i.e.independent of alloy chemistry),is made possible by using ultrasonic,magnetic or pulsed magnetic and electr...The formation of fine,non-dendritic equiaxed grains throughout a casting without the addition of refiners(i.e.independent of alloy chemistry),is made possible by using ultrasonic,magnetic or pulsed magnetic and electric current pulse techniques.The dominant mechanisms proposed for the grain refinement produced during the application of an external field are cavitation phenomena assisted nucleation or fragmentation of dendrites(ultrasonic field),wall crystals arising from the cold surface of the mould(electric current pulse,magnetic and pulsed magnetic fields).In all these cases fluid flow provides an additional contribution(e.g.reduced temperature gradients,growth rate and remelting of dendrites)to maintaining an equiaxed grain structure.The origin of equiaxed grains under an external field also depends on the casting conditions(volume and shape of casting)and the type of alloy other than the mechanisms specific to a particular technique.The current work aims to provide a detailed understanding of the various factors and mechanisms that influence the grain refinement achieved during the solidification of pure metals(magnesium and zinc)subjected to Ultra Sonic Treatment(UST).The role of the temperature range of UST application,time duration and an unpreheated sonotrode are examined with respect to the origin,evolution of equiaxed grain structure,morphology and the columnar to equiaxed transition.The origin of grains was analysed from three fundamental aspects that contribute to refinement(i)heterogeneous nucleation(ii)fragmentation of existing dendrites and(iii)grains produced from the colder surfaces(arising from mould walls or vibrating surfaces as wall crystals).A comparison of UST refinement with mechanical,low-frequency vibration,electric current pulse and magnetic field solidification of pure metals has also been provided to highlight the importance of the cold surfaces(sonotrode and mould wall)in influencing grain refinement.展开更多
To determine biochemical changes during the germination of rice grains （Oryza sativa L. subsp, indica var. Mottaikaruppan） and to improve germination rate using gibberellic acid and surfactants [sodium dodecyl sulfa...To determine biochemical changes during the germination of rice grains （Oryza sativa L. subsp, indica var. Mottaikaruppan） and to improve germination rate using gibberellic acid and surfactants [sodium dodecyl sulfate （SDS） （1.0 g/L） and Triton-X-100 （1.0 mL/L）], whole rice grains soaked in distilled water for 12 h at 30℃were germinated in the dark at 30℃ for five days. The highest germination rate （77.1%） was obtained on the 5th day. An increase in the content of reducing sugars from 7.3 to 58.1 mg/g DM （dry matter） was observed from the 1st day of germination. Free amino acids and soluble protein contents increased to 3.69 and 5.29 mg/g DM, respectively on the 5^th day of germination. Total protein content decreased from 100.5 to 91.0 g/kg DM during germination. Increases in amylolytic （1.1 to 190.0 U/g DM） and proteolytic （0 to 0.12 U/g DM） activities were observed during germination. Effects of different concentrations of gibberellic acid on the germination of rice grains were evaluated and 0.1 g/L was found to promote germination. When effects of gibberellic acid （0.1 g/L） and surfactants were evaluated individually and together, higher germination rate was observed in the control experiment （grains germinated in distilled water）, whereas giberellic acid and surfactants decreased the germination rate. Therefore, the flour obtained from the grains germinated for four days using distilled water to obtain high content of soluble materials and enzyme activities can be used in preparation of bakery items.展开更多
Objective It has long been controversial that whether authigenic chlorite coatings in sandstone reservoirs can prevent precipitation of siliceous cements. It is commonly believed that chlorite coatings （also called c...Objective It has long been controversial that whether authigenic chlorite coatings in sandstone reservoirs can prevent precipitation of siliceous cements. It is commonly believed that chlorite coatings （also called chlorite films, chlorite linings, or chlorite rims） may prevent quartz overgrowth, and thus help the preservation of original pores in sandstone reservoirs. Recently, however, this assumption has been challenged by reservoir geologists. This dispute cannot be solved by mere analysis of thin sections, nor by chemical equations and diagenesis analysis. The main objective of the present contribution is to shed light on this problem on the basis of sandstone samples from the Permian Shanxi and Shihezi Formations in the eastern part of the Sulige gas field, Ordos Basin in central China.展开更多
基金support from the Grain,Oil,and Food Engineering Technology Research Center of the State Grain and Reserves Administration/Key Laboratory of Henan Province(GO202206)the Cultivation Program for Young Backbone Teachers at Henan University of Technology+3 种基金the Key R&D Projects in Henan Province(231111113300)Double First-Class Discipline Construction Program of Henan University of Technology(0517-24410014)National Key Research and Development Program of China(2023YFF1104600)Joint Research Fund for science and technology R&D Projects of Henan Province(225200810066).
文摘Fusarium graminearum(F.graminearum)is a severe phytopathogen threatening agriculture production and food security.Paeonol,serves as a plant-derived natural component,is a promising antifungal agent.At a concentration of 0.3125 mg/mL,paeonol was adequate to fully inhibit the growth of F.graminearum mycelia within 3 days.Fourier-Transform Infrared Spectroscopy(FT-IR)analysis showed that paeonol had no impact on the outer surface of F.graminearum cell walls.While propidium iodide staining,extracellular conductivity,and pH value measurements demonstrated that paeonol disrupted the cell membrane.Furthermore,lipid oxidation and osmotic stress responses were observed in F.graminearum treated with paeonol,resulting in a 47.23%rise in malondialdehyde(MDA)levels and a 515.43%increase in glycerol levels.Moreover,on the 7th day after exposure to paeonol treatment,the deoxynivalenol(DON)level was significantly reduced,measuring only onefifth of that in the control group.Finally,paeonol was shown to inhibit F.graminearum on wheat grains and steamed bread slices.These results,for the first time,revealed the inhibitory mode of action of paeonol against F.graminearum as reflected by disruption of cell membrane integrity,induction of lipid oxidation and osmotic pressure,as well as DON biosynthesis.Furthermore,this study provided scientific evidence for the potential applications of paeonol in agriculture and food industry.
基金support from the National Natural Science Foundation of China(Grant Nos.52301137,51974097,52364050)the Natural Science Special Foundation of Guizhou University(No.(2023)20)+1 种基金Guizhou Province Science and Technology Project(Grant Nos.[2023]001,[2019]2163)Guiyang city Science and Technology Project(Grant No.[2023]48-16).
文摘The dynamic mechanical response and deformation mechanism of magnesium-yttrium alloy at high strain rate were investigated using split-Hopkinson pressure bar(SHPB)impact,and the microstructure evolution and crack formation mechanism were revealed.The yield strength and work hardening rate increase significantly with increasing impact strain rate.Deformation twinning and non-basal dislocation slip are the primary deformation mechanisms during testing.Contrary to crack initiation mechanism facilitated by adiabatic shear bands,we find that high-density co-axial nanocrystalline grains form near cracks,which leads to local softening and promotes crack initiation and rapid propagation.Most grains have similar<1^(-)21^(-)0>orientations,with unique misorientation of 24°,32°,62°,78°and 90°between adjacent grains,suggesting that these grains are primarily formed by interface transformation,which exhibits distinct differences from recrystallized grains.Our results shed light upon the dynamic mechanical response and crack formation mechanism in magnesium alloys under impact deformation.
基金supported by the National Key Re-search and Development Project of China(No.2023YFC3108400).
文摘Bioremediation has gained significant attention due to its potential to remove azo dyes.However,the challenges microor-ganisms face in surviving when azo dyes are the sole carbon source limit its widespread application.This study aimed to improve the biodegradation of azo dyes by utilizing Baijiu distiller’s grains leachate(BDGL)as a co-substrate.The experimental results demon-strated that BDGL significantly enhanced Providencia rettgeri’s ability to degrade the model pollutant Acid Black 210(AB210),achieving a decolorization efficiency of 94.5%.This may be attributed to the nutrient-rich composition of BDGL,which includes ethanol and protein,providing a favorable substrate for bacterial growth and activity.The higher biomass and increased activities of azoreductase and quinone oxidoreductase in the BDGL group further supported these findings.Additionally,this method demonstra-ted broad-spectrum degradation of azo dyes(Direct Red 5B,Acid Red 73,and Congo Red)with different structures,highlighting its potential applicability.Metabolite assays combined with transcriptomics analyses revealed that the expression of functional genes re-lated to redox reactions,azo bond cleavage,and hydrolysis increased under the co-metabolic conditions of BDGL,resulting in stronger reducing power that further mineralized the dye into smaller metabolites.Our study offers a practical strategy for the simulta-neous treatment of dye-containing wastewater and Baijiu distiller’s grains,with significant environmental and industrial applications.
基金supported by the earmarked fund for‘Pioneer’and‘Leading Goose’R&D Program of Zhejiang Province,China(Grant No.2023C02014)the Central Public Interest Scientific Institution Basal Research Fund for the China National Rice Research Institute(Grant No.CPSIBRF-CNRRI-202407).
文摘Rice is a well-recognized accumulator of arsenic(As),which poses a threat to food security and human health.Different rice varieties vary widely in their As accumulation and tolerance,yet the underlying genetic basis remains unknown.In this study,we isolated a rice mutant hag1,which displayed high accumulation of As in rice grains and increased sensitivity to As toxicity.Using genetic investigation,we identified the ATP-binding cassette(ABC)transporter OsABCC1,involved in sequestering As in vacuoles,as the causal gene responsible for As allocation and tolerance in rice.Detailed physiological analysis revealed that As stress caused more severe oxidative damage in hag1 compared with the wild type(WT).The hag1 mutant displayed different accumulation patterns depending on the levels of As stress.We discovered that under low As concentration,hag1 synthesized more thiol compounds and exhibited lower As translocation than the WT;however,at high As levels,hag1 produced fewer thiol compounds and increased As transfer factor.Transcriptome analysis of the node nearest to the panicles revealed that OsABCC1 was down-regulated in hag1,resulting in increased As translocation and accumulation in rice grains.Additionally,natural variations in the promoter of OsABCC1 may confer differential gene expression and distinct As accumulations in grains between japonica and indica rice varieties,providing insights for breeding low-As rice varieties.
基金supported by the National Key Research and Development Program of China(Nos.2022YFB3706901,2022YFB3706903)the National Natural Science Foundation of China(No.52274382)。
文摘Hot compression experiments were conducted under conditions of deformation temperatures ranging from 950 to 1150℃,strain rates of 0.001-10 s^(-1),and deformation degrees ranging from 20%to 80%.The hot deformation behavior and microstructure evolution of millimeter-grade coarse grains(MCGs)in the as-cast Ti-6Cr-5Mo-5V-4Al(Ti-6554)alloy were studied,and a hot processing map was established.Under compression along the rolling direction(RD),continuous dynamic recrystallization(CDRX)ensues due to the progressive rotation of subgrains within the MCGs.Along the transverse direction(TD),discontinuous dynamic recrystallization(DDRX)resulting from grain boundary bulging or bridging,occurs on the boundaries of the MCGs.With decreasing strain rate,increasing temperature,and higher deformation degree,dynamic recrystallization becomes more pronounced,resulting in a reduction in the original average grain size.The optimal processing parameters fall within a temperature range of 1050-1150℃,a strain rate of 0.01 s^(-1),and a deformation degree between 40%and 60%.
基金supported by the National Natural Science Foundation of China(No.41977199).
文摘In this study,two wheat-derived cadmium(Cd)-immobilizing endophytic Pseudomonas paralactis M14 and Priestia megaterium R27 were evaluated for their effects on wheat tissue Cd uptake under hydroponic conditions.Then,the impacts of the biochar(BC),M14+R27(MR),and BC+MR treatments on wheat Cd uptake and the mechanisms involved were investigated at the jointing,heading,and mature stages of wheat plants under field-plot conditions.A hydroponic experiment showed that the MR treatment significantly decreased the above-ground tissue Cd content compared with theM14 or R27 treatment.The BC+MRtreatment reduced the grain Cd content by 51.5%-67.7%and Cd translocation factor at the mature stage of wheat plants and increased the organic matter-bound Cd content by 31%-75%in the rhizosphere soils compared with the BC or MR treatment.Compared with the BC or MR treatment,the relative abundances of the biomarkers associated with Gemmatimonas,Altererythrobacter,Gammaproteobacteria,Xanthomonadaceae,Phenylobacterium,and Nocardioides in the BC+MR-treated rhizosphere microbiome decreased and negatively correlated with the organic matter-bound Cd contents.In the BC+MR-treated root interior microbiome,the relative abundance of the biomarker belonging to Exiguobacterium increased and negatively correlated with the Cd translocation factor,while the relative abundance of the biomarker belonging to Pseudonocardiaceae decreased and positively correlated with the Cd translocation factor.Our findings suggested that the BC+MR treatment reduced Cd availability and Cd transfer through affecting the abundances of these specific biomarkers in the rhizosphere soil and root interior microbiomes,leading to decreased wheat grain Cd uptake in the contaminated soil.
基金Supported by the National Natural Science Foundation Program(30160010)~~
文摘[Objective] The aim is to study the construction of vectors expressing foreign protein in potato starch grains specifically, and provide some reference for solving industrialized core problem of high cost and low expression level of foreign protein. [Method] By using molecular biological techniques of RT-PCR and nested PCR, plant expression vector for the foreign protein locating in the potato starch grains was constructed. [ Result] Coding sequence （ GC20 ） of potato starch grains that was located and expressed by GBSSI promoter was cloned. Plant expression vector was screened out through connection, transformation and enzyme digestion identification. [ Conclusion] This result laid a foundation for further screening the foreign protein on the potato starch grains.
基金Project(10964004) supported by the National Natural Science Foundation of ChinaProject(20070731001) supported by Research Fund for the Doctoral Program of China+1 种基金 Project(096RJZA104) supported by the Natural Science Foundation of Gansu Province,ChinaProject(SB14200801) supported by the Doctoral Fund of Lanzhou University of Technology,China
文摘The random distribution problem of dendrite preferred growth direction was settled by random grid method.This method was used to study the influence of forced laminar flow effect on multiple grains during solidification.Taking high pure succinonitrile （SCN） undercooled melt as an example,the forced laminar flow effect on multiple grains was studied by phase-field model of single grain which coupled with flow equations at non-isothermal condition.The simulation results show that the random grid method can reasonably settle the problem of random distribution and is more effective.When the solid fraction is relatively low,melt particles flow around the downstream side of dendrite,and the flow velocity between two dendrite arms becomes high.At the stage of solidification time less than 1800Δt,every dendrite grows freely;the upstream dendrites are stronger than the downstream ones.The higher the melt flow rate,the higher the solid fraction.However,when the solid fraction is relatively high,the dendrite arm intertwins and only a little residual melt which is not encapsulated can flow;the solid fraction will gradually tend to equal to solid fraction of melt without flow.
基金Foundation of Northwest Institute for Non-ferrous Metal Research(YK2020-9,ZZXJ2203)Capital Projects of Financial Department of Shaanxi Province(YK22C-12)+4 种基金National Natural Science Foundation of China(62204207)Innovation Capability Support Plan in Shaanxi Province of China(2022KJXX-82,2023KJXX-083)Natural Science Foundation of Shaanxi Province(2022JQ-332)Shaanxi Innovative Research Team for Key Science and Technology(2023-CX-TD-46)Key Research and Development Projects of Shaanxi Province(2024GX-YBXM-351)。
文摘Compared with Cu/Al_(2)O_(3)composites,high-strength Cu/Al_(2)O_(3)composites usually exhibit obviously deteriorated electrical conductivity.A chemical and mechanical alloying-based strategy was adopted to fabricate ultrafine composite powders with lowcontent reinforcement and constructed a combined structure of Cu ultrafine powders covered with in-situ Al_(2)O_(3)nanoparticles.After consolidation at a relatively lower sintering temperature of 550℃,high-volume-fraction ultrafine grains were introduced into the Cu/Al_(2)O_(3)composite,and many in-situ Al_(2)O_(3)nanoparticles with an average size of 11.7±7.5 nm were dispersed homogeneously in the Cu grain.Results show that the composite demonstrates an excellent balance of high tensile strength(654±1 MPa)and high electrical conductivity(84.5±0.1%IACS),which is ascribed to the synergistic strengthening effect of ultrafine grains,dislocations,and in-situ Al_(2)O_(3)nanoparticles.This approach,which utilizes ultrafine composite powder with low-content reinforcement as a precursor and employs low-temperature and high-pressure sintering subsequently,may hold promising potential for large-scale industrial production of high-performance oxide dispersion strengthened alloys.
基金supported by the National Key Research and Development Program of China(2022YFD2300700)the National Natural Science Foundation of China(32201894)+1 种基金Hainan Provincial Natural Science Foundation of China(323QN193)Rothamsted Research receives strategic funding from the Biotechnological and Biological Sciences Research Council of the UK.Matthew J.Paul acknowledges funding from the Delivering Sustainable Wheat(BB/X011003/1)Strategic Program.
文摘Inferior grains exhibit delayed developmental processes and reduced metabolic activities compared to superior grains,leading to unstable rice yield and quality.While significant advancements have been achieved in elucidating the physiology of endosperm filling in inferior grains,the role of the embryo remains underexplored and warrants comprehensive investigation.Two Wuyujing 3 mutants,DW024(relatively synchronous;syn-DW024)and DW179(significantly asynchronous;asyn-DW179),with different grain-filling patterns were used in this study.Samples of superior and inferior grains were collected at intervals from 5 to 60 d after fertilization and subsequently dissected into subsamples of the embryo and endosperm.Histochemical staining,biochemical analysis,and RNA sequencing(RNA-seq)were combined to systematically compare developmental and physiological traits between superior and inferior grains.Combining hierarchical clustering of mRNA datasets revealed three developmental phases of the endosperm and embryo:morphogenesis,endosperm filling/embryo enlargement,and maturation.In both syn-DW024 and asyn-DW179,the duration of the endosperm/embryo morphogenesis phase was identical in superior and inferior grains.The inferior grains of asyn-DW179 exhibited a 10-day prolongation in the endosperm filling phase and a 20-day extension in the embryo enlargement phase compared to the superior grains.The endosperm of inferior grains exhibited higher contents of sugars and free amino acids,along with slower accumulation of storage compounds,which was associated with the down-regulation of genes for starch synthesis and ABA signaling.In addition,transporters for nutrient exchanges between endosperm and embryo were down-regulated,suggesting a potential role of the embryo in adjusting the endosperm filling process.Collectively,our results reveal that the prolonged phases of endosperm filling and embryo enlargement may underlie the impaired development of inferior grains,offering a new perspective for breeding or cultivating rice with uniform grain quality.
基金supported by the National Key Research and Development Program of China(2023YFE0111800)Shaanxi Livestock and Poultry Breeding Double-chain Fusion Key Project(grant number 2022GD-TSLD-46-0501)。
文摘Background The diverse types and processing methods of grains intricately influence the sites and digestibility of starch digestion,thereby impacting energy utilization.This study aimed to explore the impact of grain variety and processing methods on the net energy(NE)in dairy goats,analyzing these effects at the level of nutrient digestion and metabolism.Methods Eighteen castrated Guanzhong dairy goats(44.25±3.59 kg BW)were randomly divided into 3 groups,each consisting of 6 replicates.The substitution method was employed to determine the NE values of the dry-rolled corn(DRC),dry-rolled wheat(DRW)or steam-flaked corn(SFC,360 g/L).Briefly,two phases were performed.Throughout the basal phase,all goats were fed the same basal diet.In the substitution phase,30%of the basal diet was replaced with DRC,DRW and SFC,respectively.Results In this study,the NE values of the DRC,DRW and SFC were 7.65,7.54 and 7.44 MJ/kg DM,respectively.Compared to the DRC group,the DRW group showed increased digestibility of starch and crude protein(CP).Similarly,the SFC group exhibited increased organic matter(OM)and starch digestibility and a trend towards higher dry matter(DM)digestibility,reduced fecal OM and starch content.Additionally,fecal volatile fatty acid(VFA)concentrations decreased in goats fed SFC.Correspondingly,digestible energy(DE)in the DRW and SFC groups tended to be higher than in the DRC group.DRW increased total VFA concentration compared to DRC,while SFC increased the proportion of propionate and decreased the acetate-to-propionate ratio in the rumen.Both the DRW and SFC diets elevated serum glucose levels.Furthermore,heat increment(HI)and gaseous energy(Gas E)related to fermentation were significantly higher in the DRW and SFC groups compared to the DRC group.Conclusion Our findings indicated that DRW and SFC increased rumen starch fermentation in goats,thereby improving total tract starch digestion and DE.However,DRW and SFC failed to improve NE value due to increased heat and gas energy production from fermentation.Therefore,excessively refined grains processing in the diet of dairy goats does not effectively improve energy efficiency.
基金Project supported by the Natural Science Foundation of Hunan Province(2024JJ4056)the Key Project of Guangxi Zhuang Autonomous Region(AB22080089)the Government of Chongzuo,Guangxi Zhuang Autonomous Region(FA20210716)。
文摘The rapid development of magnetic materials provides the possibility for the application of permanent magnet stirring(PMS).Numerical and experimental investigations were employed with respect to the solidification process of the Al—2Sc alloy controlled by a novel PMS using NdFeB permanent magnets under various rotation speeds(0,50,100 and 150 r/min).The simulated results reveal that the maximum electromagnetic force increases proportionally from 4.14 to 12.39 kN/m^(3)and the maximum tangential velocity increases from 0.13 to 0.36 m/s when the rotation speed of PMS enhances from 50 to 150 r/min in the ingot melt.Besides,the experimental results demonstrate that PMS can achieve a uniform distribution of blocky Al_(3)Sc precipitated phase in the longitudinal direction under the impact of a forced fluid flow.Moreover,increasing rotation speed of PMS is beneficial to refining aluminum grain size significantly and decreasing the texture intensity in the alloy.In addition,the Brinell hardness of Al-2Sc alloy is increased by 33%to 27.8 HB and the tensile strength is enhanced by 34%-128.2 MPa,due to the improved distribution of the strengthening Al_(3)SC phase and the grain refinement of Al matrix under the impact of PMS.This work provides an effective application of NdFeB permanent magnets in the metal cast field.
基金financially supported by the National Natural Science Foundation of China(No.52202136)the Natural Science Foundation of Jiangxi Province(No.20232BAB204017)+2 种基金the State Key Laboratory of Electrical Insulation and Power Equipment(No.EIPE24203)Guangdong Provincial Key Laboratory of Electronic Functional Materials and Devices(No.EFMD2024002Z)the Innovation Special Foundation Project for Graduate Students of Nanchang Hangkong University(No.YC2024019)
文摘Copper calcium titanate(CaCu_(3)Ti_(4)O_(12),CCTO)ceramics with colossal permittivity have gained widespread concern because of their potential application in modern electronic devices with miniaturization and integration.However,the extent of grain and grain boundary contribution to the colossal permittivity of CCTO-based ceramics based on the internal barrier layer capacitor(IBLC)model is still in debate.This affects their electrical performance optimization and real-world applications.In this study,a series of novel lead-free colossal permittivity ceramic s,xLiCuNb_(3)O_(9-)(1-x)CaCu_(3)Ti_(4)O_(12)(LCNOCCTO),were designed and prepared using a solid-phase reaction approach.The colossal permittivity response mechanism of LCNO-CCTO ceramics was further explored by performing the complex impedance spectrum and analyzing the activation energy from the grain and grain boundary contribution viewpoint.As a result,the LCNO-CCTO ceramics present the cubic perovskite structure with the space groups of■.All the LCNOCCTO ceramics exhibit the significantly enhanced colossal permittivity(10^(5))response,and the ceramic with x=0.15 shows the highest permittivity of about 4.64×10^(5)(20 Hz,room temperature)accompanied by a lower grain resistance of 9.61Ωand larger grain activation energy of 0.21 eV.The enhanced colossal permittivity response is primarily attributed to the great electrical response inside grains of LCNO-CCTO ceramics,resulting from a smaller grain resistance.Also importantly,the high-frequency dielectric relaxation characteristics are improved by incorporating the LCNO into CCTO ceramics as an ion form.Accordingly,the LCNO-CCTO ceramics show a suppressed high-frequency dielectric loss.These results can provide a thorough knowledge and useful optimization strategy for developing high-performance colossal permittivity materials.
基金Supported by the Fundamental Research Funds for the Central Universities (SWJTU09BR221)~~
文摘[Objective] The aim was to study characters of pollen grains of tetraploid lines and diploid control line of Chrysanthemum cinerariifolium (Trev.) Vis.,morphological characters,fertility of pollen grain and germination percentage of seeds. [Method] Pollen grains were prepared by sulphuric acid-acetyl oxide decomposition method. The lengths of polar axis and equatorial axis of pollen grains were determined with general optical microscope. The morphology of pollen grains was observed with SEM (scanning electron microscope) and the typical visual fields of 2 500× (or 2 000×),7 000× were taken pictures. [Result] Comparing with the diploid control line,the pollen grains of five tetraploid lines which were tested were different from the diploid line in morphology,sculpture,etc.. 4 of the 5 tested samples were significant larger than the diploid line in size and one was similar to the diploid line. [Conclusion] This research provided references for breeding tetraploid improved varieties of Chrysanthemum cinerariifolium (Trev.) Vis. with good fertility and high germination percentage.
文摘Cytochemical and ultrastructural studies indicated that compound spherical bodies observed near the sieve plate in the sieve tube members during the period of cambial dormancy in the shoots of Eucommia ulmoides Oliv. were polysaccharide bodies different from the polysaccharide grains in other parenchyma cells in shoots, and were similar to cell walls in their staining properties. The compound spherical bodies occurred in the sieve elements during the period of cambial rest and disappeared in the sieve elements during the period of cambial quiescence and activity.
文摘In cross sections by microscopic studies have examined the features of the shell thickness grains, cells, aleuronic layer and endosperm in the species T. dicoccum Schuebl., sorts Mironovskaya-808 and their interspecific hybrids F9 （alloplasmatic lines）. The result of studies showed the specific and varietal differences, and differences in hybrid plants on linear parameters size grains, the degree of specificity of the shells grains of wheat and identified species and varietal differences as well as differences among hybrids in the linear dimensions of the cells of the aleuronic layer. It is shown that among the studied forms of wheat allocated species T. dicoccum Shuebl. and the lines D-N-05, D-F-05 and D-40-05-KhNA with relatively large grains, a well-developed endosperm, most of thin shells and large grain aleurone layer cells. They are of most interest for further breeding research in terms of nutritional value.
基金supported by the Hunan Provincial Natural Science Foundation of China (No. 2017JJ3380)the National Natural Science Foundation of China (No. 51775564)+3 种基金the State key Laboratory of High Performance Complex Manufacturing (No. zzyjkt2014-01)the Open-End Fund for the Valuable and Precision Instruments of Central South University (No. CSUZC201821)Hebei Iron and Steel Joint Funds (No. E2015209243)the Fundamental Research Funds for the Central Universities of Central South University (No. 153711025)
文摘In authors’ previous work [Mater. Charact. 141 (2018) 212-222]. it was found that the heterogeneous deformed microstructures can be replaced by the relatively homogeneous recrystallized grains through an annealing treatment. However, there are still some relatively large recrystallized grains. To find the reasons for the formation of large grains, some new annealing treatment tests were done, and the cellular automation (CA) simulations were carried out in the present work. The experimental results showed that the microstructural evolution during annealing treatment is significantly affected by the content of S phase. So. the effects of δ phase on the nucleation and growth of grains are carefully considered in the CA model to accurately simulate the microstructural evolution behavior. By the CA simulation, it is found that the dislocation density rapidly decreases due to the nucleation of static recrystallization (SRX) and the growth of dynamc recrystallization (DRX) nuclei at the early stage of annealing. The high initial dislocation density provide the high velocity for the growth of DRX nuclei, which is responsible for the formation of coarse grains, However, the growth rate of SRX nuclei is relatively small due to the low dislocation density and pinning effects of δ phase.
基金funding support provided by the Australian Research Council Research Hub for Advanced Manufacturing of Medical Devices IH150100024the ARC Discovery grant DP140100702ARC linkage project LP150100950。
文摘The formation of fine,non-dendritic equiaxed grains throughout a casting without the addition of refiners(i.e.independent of alloy chemistry),is made possible by using ultrasonic,magnetic or pulsed magnetic and electric current pulse techniques.The dominant mechanisms proposed for the grain refinement produced during the application of an external field are cavitation phenomena assisted nucleation or fragmentation of dendrites(ultrasonic field),wall crystals arising from the cold surface of the mould(electric current pulse,magnetic and pulsed magnetic fields).In all these cases fluid flow provides an additional contribution(e.g.reduced temperature gradients,growth rate and remelting of dendrites)to maintaining an equiaxed grain structure.The origin of equiaxed grains under an external field also depends on the casting conditions(volume and shape of casting)and the type of alloy other than the mechanisms specific to a particular technique.The current work aims to provide a detailed understanding of the various factors and mechanisms that influence the grain refinement achieved during the solidification of pure metals(magnesium and zinc)subjected to Ultra Sonic Treatment(UST).The role of the temperature range of UST application,time duration and an unpreheated sonotrode are examined with respect to the origin,evolution of equiaxed grain structure,morphology and the columnar to equiaxed transition.The origin of grains was analysed from three fundamental aspects that contribute to refinement(i)heterogeneous nucleation(ii)fragmentation of existing dendrites and(iii)grains produced from the colder surfaces(arising from mould walls or vibrating surfaces as wall crystals).A comparison of UST refinement with mechanical,low-frequency vibration,electric current pulse and magnetic field solidification of pure metals has also been provided to highlight the importance of the cold surfaces(sonotrode and mould wall)in influencing grain refinement.
文摘To determine biochemical changes during the germination of rice grains （Oryza sativa L. subsp, indica var. Mottaikaruppan） and to improve germination rate using gibberellic acid and surfactants [sodium dodecyl sulfate （SDS） （1.0 g/L） and Triton-X-100 （1.0 mL/L）], whole rice grains soaked in distilled water for 12 h at 30℃were germinated in the dark at 30℃ for five days. The highest germination rate （77.1%） was obtained on the 5th day. An increase in the content of reducing sugars from 7.3 to 58.1 mg/g DM （dry matter） was observed from the 1st day of germination. Free amino acids and soluble protein contents increased to 3.69 and 5.29 mg/g DM, respectively on the 5^th day of germination. Total protein content decreased from 100.5 to 91.0 g/kg DM during germination. Increases in amylolytic （1.1 to 190.0 U/g DM） and proteolytic （0 to 0.12 U/g DM） activities were observed during germination. Effects of different concentrations of gibberellic acid on the germination of rice grains were evaluated and 0.1 g/L was found to promote germination. When effects of gibberellic acid （0.1 g/L） and surfactants were evaluated individually and together, higher germination rate was observed in the control experiment （grains germinated in distilled water）, whereas giberellic acid and surfactants decreased the germination rate. Therefore, the flour obtained from the grains germinated for four days using distilled water to obtain high content of soluble materials and enzyme activities can be used in preparation of bakery items.
基金supported by the National Natural Science Foundation of China(grant No.41402120)Shandong University of Science and Technology Research Fund(grant No.2015TDJH101)
文摘Objective It has long been controversial that whether authigenic chlorite coatings in sandstone reservoirs can prevent precipitation of siliceous cements. It is commonly believed that chlorite coatings （also called chlorite films, chlorite linings, or chlorite rims） may prevent quartz overgrowth, and thus help the preservation of original pores in sandstone reservoirs. Recently, however, this assumption has been challenged by reservoir geologists. This dispute cannot be solved by mere analysis of thin sections, nor by chemical equations and diagenesis analysis. The main objective of the present contribution is to shed light on this problem on the basis of sandstone samples from the Permian Shanxi and Shihezi Formations in the eastern part of the Sulige gas field, Ordos Basin in central China.
