The protein content and amino acid composition for 17 wheat-related species （WRS） and three common wheats （control） were determined and analyzed, and the essential amino acids （EAAs） in WRS were evaluated accord...The protein content and amino acid composition for 17 wheat-related species （WRS） and three common wheats （control） were determined and analyzed, and the essential amino acids （EAAs） in WRS were evaluated according to FAO/WHO amino acid recommendations. The results showed that the mean protein content for WRS was 16.67%, which was 23.21% higher than that for the control. The mean contents （g 100 g^-1 protein） of most amino acids for WRS were lysine 2.74%, threonine 2.83%, phenylalanine 4.17%, isoleucine 3.42%, valine 3.90%, histidine 2.81%, glutamic acid 29.96%, proline 9.12%, glycine 3.59%, alanine 3.37%, and cysteine 1.57%, which were higher than those for the control. The contents of the other 6 amino acids for WRS were lower than those for the control. The materials （Triticum monococcum L., Triticum carthlicum Nevski, and Triticum turgidum L.） contained relatively high concentration of the most deficient EAAs （lysine, threonine, and methionine）. Comparing with FAO/WHO amino acid recommendations, the amino acid scores （AAS） of lysine （49.8%）, threonine （70.7%）, and sulfur-containing amino acids （74.8%） were the lowest, which were considered as the main limiting amino acids in WRS. It was observed that the materials with Triticum urartu Turn. （AA） and Aegilops speltoides Tausch. （SS） genomes had relatively high contents of protein and EAA. The contents of protein （16.91%）, phenylalanine （4.78%）, isoleucine （3.53%）, leucine （6.16%）, and valine （4.09%） for the diploid materials were higher than those for the other materials. These results will provide some information for selecting parents in breeding about nutrient quality and utilization of fine gene in wheat.展开更多
Iron and manganese are the important redoxsensitive elements in the ocean. Previous studies have established a series of paleo-depositional redox proxies based on the form and content of iron in sedimentary rocks(e.g....Iron and manganese are the important redoxsensitive elements in the ocean. Previous studies have established a series of paleo-depositional redox proxies based on the form and content of iron in sedimentary rocks(e.g., degree of pyritization, FeHR/FeT, Fe/Al). These proxies were developed and applied on siliciclastic-rich marine sediments. Although marine carbonate rocks are generally considered to preserve the geochemical signals of ancient seawater, neither Fe nor Mn content in marine carbonate rocks(Fecarb, Mncarb) has been independently used as a proxy to quantify environmental cues in paleo-oceans. Both Fe and Mn are insoluble in oxic conditions(Fe_2O_3, Fe(OH)_3,MnO_2), while their reduced forms(Fe^(2+) and Mn^(2+)) are soluble. Therefore, oxic seawater should have low concentrations of dissolved Fe^(2+)and Mn^(2+), and accordingly carbonate rocks precipitated from oxic seawater should have low Fecarband Mncarb, and vice versa. To evaluate whether Fecarband Mncarbcan be used to quantify oxygen fugacity in seawater, we measured Fecarband Mncarbof Upper Devonian marine carbonate rocks collected from nine sections in South China. Fecarbof intraplatform basin samples wassignificantly higher than that of shelf samples, while shelf and basin samples had comparable Mncarb. The modeling result indicates that the dramatic difference in Fecarbcannot be explained by variation in oxygen fugacity between the shelf and basin seawater. Instead, both Fecarband Mncarb appear to be more sensitive to benthic flux from sediment porewater that is enriched in Fe^(2+)and Mn^(2+). Porewater Fe^(2+)and Mn^(2+)derive from bacterial iron and manganese reduction; flux was controlled by sedimentation rate and the depth of the Fe(Mn) reduction zone in sediments, the latter of which is determined by oxygen fugacity at the water–sediment interface. Thus, high Fecarbof the basin samples might be attributed to low sedimentation rate and/or low oxygen fugacity at the seafloor. However, invariant Mncarbof the shelf and basin samples might be the consequence of complete reduction of Mn in sediments. Our study indicates that marine carbonate rocks may not necessarily record seawater composition, particularly for benthic carbonate rocks. The influence of benthic flux might cause carbonate rocks' geochemical signals to deviate significantly from seawater values. Our study suggests that interpretation of geochemical data from carbonate rocks, including carbonate carbon isotopes, should consider the process of carbonate formation.展开更多
Abundant landslide deposits were triggered by the Wenchuan earthquake, providing a rich source of material for subsequent debris flows or slope failures under rainfall conditions. A good understanding of the physical ...Abundant landslide deposits were triggered by the Wenchuan earthquake, providing a rich source of material for subsequent debris flows or slope failures under rainfall conditions. A good understanding of the physical and mechanical properties of the landslide deposits is very important to the research on slope failure mechanisms and the initiation of debris flow. Laboratory biaxial compression tests are used to study the material compositions and water content impacts on the mechanical properties of landslide deposits, and a discrete element method （a bond-contact model） is used to study the particle stiffness, bond force, friction coefficient and confining stress impact on the mechanical behaviors and the relationships between the numerical and experimental parameters. The experimental results show that the failure stress of landslide deposits is decreased with increasing content of fine particles and also with increased water content, especially at the initial increasing stage. Cohesion of the saturated landslide deposits is increased, but the friction angle is decreased with the increase in the fine particle content. Shear strength parameters （the cohesion and friction angle） are decreased with the increasing water content at the initial increasing stage, and then, they slowly decrease. There is a critical value of the water content at 5%-7% （in weight） for the failure stress and shear strength parameters of the landslide deposits. Quadratic equations are presented to describe the relation between the bond force and cohesion, and the numerical friction coefficient and the experimental friction angle.展开更多
Brazing filler metals are widely applied,which serve as an industrial adhesive in the joining of dissimilar structures.With the continuous emergence of new structures and materials,the demand for novel brazing filler ...Brazing filler metals are widely applied,which serve as an industrial adhesive in the joining of dissimilar structures.With the continuous emergence of new structures and materials,the demand for novel brazing filler metals is ever-increasing.It is of great significance to investigate the optimized composition design methods and to establish systematic design guidelines for brazing filler metals.This study elucidated the fundamental rules for the composition design of brazing filler metals from a three-dimensional perspective encompassing the basic properties of applied brazing filler metals,formability and processability,and overall cost.The basic properties of brazing filler metals refer to their mechanical properties,physicochemical properties,electromagnetic properties,corrosion resistance,and the wettability and fluidity during brazing.The formability and processability of brazing filler metals include the processes of smelting and casting,extrusion,rolling,drawing and ring-making,as well as the processes of granulation,powder production,and the molding of amorphous and microcrystalline structures.The cost of brazing filler metals corresponds to the sum of materials value and manufacturing cost.Improving the comprehensive properties of brazing filler metals requires a comprehensive and systematic consideration of design indicators.Highlighting the unique characteristics of brazing filler metals should focus on relevant technical indicators.Binary or ternary eutectic structures can effectively enhance the flow spreading ability of brazing filler metals,and solid solution structures contribute to the formability.By employing the proposed design guidelines,typical Ag based,Cu based,Zn based brazing filler metals,and Sn based solders were designed and successfully applied in major scientific and engineering projects.展开更多
Sea cucumber, Apostichopus japonicus（Selenka）, is a commercially important marine species in China. Among the differently colored varieties sold in China, white and purple sea cucumbers have the greatest appeal to c...Sea cucumber, Apostichopus japonicus（Selenka）, is a commercially important marine species in China. Among the differently colored varieties sold in China, white and purple sea cucumbers have the greatest appeal to consumers. Identification of the pigments that may contribute to the formation of different color morphs of sea cucumbers will provide a scientific basis for improving the cultivability of desirable color morphs. In this study,sea cucumbers were divided into four categories according to their body color： white, light green, dark green, and purple. The pigment composition and contents in the four groups were analyzed by high performance liquid chromatography（HPLC）. The results show that the pigment contents differed significantly among the white, lightgreen, dark-green, and purple sea cucumbers, and there were fewer types of pigments in white sea cucumber than in the other color morphs. The only pigments detected in white sea cucumbers were guanine and pteroic acid.Guanine and pteroic acid are structural colors, and they were also detected in light-green, dark-green, and purple sea cucumbers. Every pigment detected, except for pteroic acid, was present at a higher concentration in purple morphs than in the other color morphs. The biological color pigments melanin, astaxanthin, β-carotene, and lutein were detected in light-green, dark-green, and purple sea cucumbers. While progesterone and lycopene,which are also biological color pigments, were not detected in any of the color morphs. Melanin was the major pigment contributing to body color, and its concentration increased with deepening color of the sea cucumber body. Transmission electron microscopy analyses revealed that white sea cucumbers had the fewest epidermal melanocytes in the body wall, and their melanocytes contained fewer melanosomes as well as non-pigmented pre-melanosomes. Sea cucumbers with deeper body colors contained more melanin granules. In the body wall of dark-green and purple sea cucumbers, melanin granules were secreted out of the cell. The results of this study provide evidence for the main factors responsible for differences in coloration among white, light-green, darkgreen, and purple sea cucumbers, and also provide the foundation for further research on the formation of body color in sea cucumber, A. japonicus.展开更多
Twenty-nine japonica rice varieties collected from Jiangsu and Zhejiang Provinces, China were planted in Hangzhou, China, to investigate the phytic acid content in brown rice and its frequency distribution as well as ...Twenty-nine japonica rice varieties collected from Jiangsu and Zhejiang Provinces, China were planted in Hangzhou, China, to investigate the phytic acid content in brown rice and its frequency distribution as well as the correlation among the contents of phytic acid, total protein and four protein compositions in brown rice. The phytic acid content in brown rice ranged from 0.699% to 1.034%, with a mean of 0.868% for the 29 tested rice varieties. Xiushui series rice varieties generally exhibited lower phytic acid level than Wuyujing and Huai series rice varieties. A rough normal distribution, with a mean of 8.722%, was observed for the total protein contents in the tested varieties. Of the four protein compositions, the glutelin, globulin and albumin contents had larger coefficient of variation than the prolamin content, although the difference in prolamin content was genotype-dependent. No significant correlation was found between the phytic acid and four protein composition contents, whereas the total protein content was significantly and positively related to the glutelin content in brown rice.展开更多
It is important to acquire the composition of Si1-xGex layer, especially that with high Ge content, epitaxied on Si substrate. Two nondestructive examination methods, double crystals X-ray diffraction （DCXRD） and mi...It is important to acquire the composition of Si1-xGex layer, especially that with high Ge content, epitaxied on Si substrate. Two nondestructive examination methods, double crystals X-ray diffraction （DCXRD） and micro-Raman measurement, were introduced comparatively to determine x value in Si1-xGex layer, which show that while the two methods are consistent with each other when x is low, the results obtained from double crystals X-ray diffraction are not credible due to the large strain relaxation occurring in Si1-xGex layers when Ge content is higher than about 20%. Micro-Raman measurement is more appropriate for determining high Ge content than DCXRD.展开更多
This study has been conducted to evaluate the influence of flux composition on the microstructure and oxygen content of the low carbon steel weldments using developed agglomerated fluxes.Ca_F2,FeMn and NiO were added ...This study has been conducted to evaluate the influence of flux composition on the microstructure and oxygen content of the low carbon steel weldments using developed agglomerated fluxes.Ca_F2,FeMn and NiO were added to the CaO-SiO_2-Al_2O_3 base fluxes in the varying amount of 2%-8% to examine the various elements transferred to the weldments.The microstructure obtained was a mixture of pearlite and ferrite contents.This study reveals that CaF_2 and Fe Mn both are having significant effect on pearlite percentage while CaF_2 and NiO are significant for oxygen transfer in the welds.The interaction effects of CaF_2 and Fe Mn and CaF_2 and Ni O are also significant to the microstructure of the welds.The fluxes were designed using response surface methodology( RSM) and were developed by agglomeration technique.展开更多
Fatty acids are the main constituents of vegetable oils.To determine the fatty acid compositions of small trade vegetable oils and some less well studied beneficial vegetable oils,and investigate their relationships w...Fatty acids are the main constituents of vegetable oils.To determine the fatty acid compositions of small trade vegetable oils and some less well studied beneficial vegetable oils,and investigate their relationships with antioxidant activity and oxidative stability,gas chromatography-mass spectrometry was performed to characterize the associated fatty acid profiles.The antioxidant activity of vegetable oils,based on their DPPH-scavenging capacity(expressed as IC_(50) values),was used to assess their impact on human health,and their oxidative stability was characterized by performing lipid oxidation analysis to determine the oxidative induction time of fats and oils.In addition,correlation analyses were performed to examine associations between the fatty acid composition of the oils and DPPH-scavenging capacity and oxidative stability.The results revealed that among the assessed oils,coffee seed oil has the highest saturated fatty acid content(355.10 mg/g),whereas Garddenia jaminoides oil has the highest unsaturated fatty acid content(844.84 mg/g).Coffee seed oil was also found have the lowest DPPH IC_(50) value(2.30 mg/mL)and the longest oxidation induction time(17.09 h).Correlation analysis revealed a significant linear relationship(P<0.05)between oxidative stability and unsaturated fatty acid content,with lower contents tending to be associated with better oxidative stability.The findings of this study provide reference data for the screening of functional edible vegetable oils.展开更多
Lightweight high/medium-entropy alloys(H/MEAs)possess attractive properties such as high strength-to-weight ratios,however,their limited room-temperature tensile ductility hinders their widespread engi-neering impleme...Lightweight high/medium-entropy alloys(H/MEAs)possess attractive properties such as high strength-to-weight ratios,however,their limited room-temperature tensile ductility hinders their widespread engi-neering implementation,for instance in aerospace structural components.This work achieved a transfor-mative improvement of room-temperature tensile ductility in Ti-V-Zr-Nb MEAs with densities of 5.4-6.5 g/cm3,via ingenious composition modulation.Through the systematic co-adjustment of Ti and V contents,an intrinsic ductility mechanism was unveiled,manifested by a transition from predominant intergranular brittle fracture to pervasive ductile dimpled rupture.Notably,the modulated deformation mechanisms evolved from solitary slip toward collaborative multiple slip modes,without significantly compromising strength.Compared to equimolar Ti-V-Zr-Nb,a(Ti1.5V)3ZrNb composition demonstrated an impressive 360%improvement in elongation while sustaining a high yield strength of around 800 MPa.Increasing Ti and V not only purified the grain boundaries by reducing detrimental phases,but also tai-lored the deformation dislocation configurations.These insights expanded the applicability of lightweight HEAs to areas demanding combined high strength and ductility.展开更多
Aseries of [(Fe_(0.6)Co_(0.2)Ni_(0.2))_(0.75-0.03x)B_(0.2)Si_(0.05+0.03x)]_(96)Nb_(4) amorphous alloy composite coatings were prepared by adjusting the silicon content(x=0,1,2,3,4,5,and 6)and their microstructures and...Aseries of [(Fe_(0.6)Co_(0.2)Ni_(0.2))_(0.75-0.03x)B_(0.2)Si_(0.05+0.03x)]_(96)Nb_(4) amorphous alloy composite coatings were prepared by adjusting the silicon content(x=0,1,2,3,4,5,and 6)and their microstructures and tribological properties were investigated by laser cladding technique.Additionally,the effect of Si on the glass forming ability(GFA)of the layers was understood.Results show that an appropriate Si content can refine the microstructure of the FeCoNiBSiNb laser cladding layers and improve the mechanical and tribological properties.The hardness of the coating layer increases monotonically with the Si content.At the Si content of 4.8at%(x=0),the coating layer exhibits a relatively low hardness(734.2HV 0.1).Conversely,at the silicon content of 13.44at%(x=3),the coating layer exhibits the highest hardness(1106HV 0.1).The non-crystalline content and tensile strength exhibit an initial increase,followed by a subsequent decrease.At x=2,the coating exhibits its maximum fracture strength(2880 MPa).However,when x>2,the fracture strength of the coating decreases with an increase in x.Conversely,with an increase in Si content,the wear volume loss initially decreases and then increases.At a Si content of 10.56at%(x=2),the coating exhibits the highest non-crystalline content(42%),the highest tensile strength(2880 MPa),and the most favorable dry friction performance.展开更多
In order to adjust some properties of cement grout or concrete,some mineral admixtures are usually added in the preparation.Admixtures can reduce the cement consumption and save the cost,and also adjust the workabilit...In order to adjust some properties of cement grout or concrete,some mineral admixtures are usually added in the preparation.Admixtures can reduce the cement consumption and save the cost,and also adjust the workability of the material,improve the strength and durability of the cement stone,or reduce hydration heat of the composite cement.At present,the content of fly ash or slag is generally less than 50%among the composite cementitious materials that have been studied more,but there is little research on composite cementitious materials with large mineral admixture.In this paper,XRD,SEM,and adiabatic temperature rise tests were used to discuss hydration products and mechanism of composite cement grout with 90%content of fly ash and slag.The results show that the hydration of the composite cement grout is an alkali-activated hydration reaction,and the hydration products are mainly amorphous substances such as hydrated calcium silicate or hydrated calcium aluminate gel.The hydration reaction temperature rise is much lower than that of ordinary cement grout,and the time of the temperature peak is significantly delayed.展开更多
With the increasing complexity of the current electromagnetic environment,excessive microwave radi-ation not only does harm to human health but also forms various electromagnetic interference to so-phisticated electro...With the increasing complexity of the current electromagnetic environment,excessive microwave radi-ation not only does harm to human health but also forms various electromagnetic interference to so-phisticated electronic instruments.Therefore,the design and preparation of electromagnetic absorbing composites represent an efficient approach to mitigate the current hazards of electromagnetic radiation.However,traditional electromagnetic absorbers are difficult to satisfy the demands of actual utilization in the face of new challenges,and emerging absorbents have garnered increasing attention due to their structure and performance-based advantages.In this review,several emerging composites of Mxene-based,biochar-based,chiral,and heat-resisting are discussed in detail,including their synthetic strategy,structural superiority and regulation method,and final optimization of electromagnetic absorption ca-pacity.These insights provide a comprehensive reference for the future development of new-generation electromagnetic-wave absorption composites.Moreover,the potential development directions of these emerging absorbers have been proposed as well.展开更多
The aim of this work was to contribute to our knowledge of the proximate composition, mineral and vitamin content of 20 edible wild plants used as spices in Cameroon. The plant species were collected from 3 different ...The aim of this work was to contribute to our knowledge of the proximate composition, mineral and vitamin content of 20 edible wild plants used as spices in Cameroon. The plant species were collected from 3 different markets in the West Region of Cameroon and analysed for their content of crude proteins, and lipid, ash, moisture, available sugars, total phenols, carotenoids, minerals (Ca, Zn, K, Na, Mg, Al, Mn, Cu and Se), and vitamins (A, E and C) as well as for their pH and colour. Results revealed that all the plants were low in moisture (7.7 to 10.5 g/100 g) but high in ash content (7.7 to 10.5 g/100 g). Hua gabonii (bark) (1594.5 mg/100 g) was relative source of calcium, Echinops giganteus (206.4 mg/100 g) exhibited the highest level of iron and Scorodophleus zenkeri (310.0 μg/100 g) the highest level of selenium. Generally all the plants were found to contain low levels of Zn, Cu and Mg. Wide variations were observed for the pro- teins and available sugars among the samples. The lipid content of some of the plants were surprisingly relatively high as was the case with Monodora myristica (53.4 g/100 g), Xylopia aethiopica (33.7 g/100 g), Fagara leprieuri (32.1 g/100 g), and Aframomum daniellii (23.1 g/100 g). All the plants were rich in phenols, carotenoids, vitamin E and C. They are dark in colour and in solution they tended to provoke a fair acidification.展开更多
To obtain solid Al2O3 or MgO·Al2O3 inclusions in ladle furnace(LF)refining process and achieve ultra-low total oxygen content in steel through subsequent Ruhrstahl Heraeus degassing,the effects of ferrosilicon al...To obtain solid Al2O3 or MgO·Al2O3 inclusions in ladle furnace(LF)refining process and achieve ultra-low total oxygen content in steel through subsequent Ruhrstahl Heraeus degassing,the effects of ferrosilicon alloy,Si content of steel,and slag basicity on the compositions of inclusions during LF refining were investigated in Al-killed steel.Al2O3 inclusions could be transformed into CaO-Al2O3-MgO-CaS inclusions after adding ferrosilicon alloy in the LF refining process as this alloy contains some CaSi alloy impurities.The addition of all ferrosilicon alloys required for the steel in the tapping process could eliminate the influence of Ca in ferrosilicon alloy on the compositions of inclusions.Si in liquid steel had a significant influence on the compositions of inclusions during LF refining when CaO-Al2O3-SiO2-MgO slag with high basicity of 7.0 was used.This was because[Ca]produced by the reaction of CaO and[Al]could be consumed more readily by SiO2 in Si-free steel than in Si-containing steel,which was confirmed by the difference of total calcium content between Si-free and Si-containing steels.As a result,Al2O3 and MgO·Al2O3 inclusions were retained in Si-free steel,whereas calcium aluminate inclusions were found in Si-containing steel.For CaO-Al2O3-SiO2-MgO slag with low basicity of 2.8,Al2O3 and MgO·Al2O3 inclusions were obtained after LF refining in Si-containing steel when all ferrosilicon alloys required for the steel were added in the tapping process.This was because the reaction of CaO and[Al]was weak,and residual[Ca]in the steel could be rapidly consumed by SiO2 in low-basicity slag owing to the low activity of CaO and high activity of SiO2,leading to a low total calcium content of 0.0003%in Si-containing steel.展开更多
Gas content serves as a critical indicator for assessing the resource potential of deep coal mines and forecasting coal mine gas outburst risks.However,existing sampling technologies face challenges in maintaining the...Gas content serves as a critical indicator for assessing the resource potential of deep coal mines and forecasting coal mine gas outburst risks.However,existing sampling technologies face challenges in maintaining the integrity of gas content within samples and are often constrained by estimation errors inherent in empirical formulas,which results in inaccurate gas content measurements.This study introduces a lightweight,in-situ pressure-and gas-preserved corer designed to collect coal samples under the pressure conditions at the sampling point,effectively preventing gas loss during transfer and significantly improving measurement accuracy.Additionally,a gas migration model for deep coal mines was developed to elucidate gas migration characteristics under pressure-preserved coring conditions.The model offers valuable insights for optimizing coring parameters,demonstrating that both minimizing the coring hole diameter and reducing the pressure difference between the coring-point pressure and the original pore pressure can effectively improve the precision of gas content measurements.Coring tests conducted at an experimental base validated the performance of the corer and its effectiveness in sample collection.Furthermore,successful horizontal coring tests conducted in an underground coal mine roadway demonstrated that the measured gas content using pressure-preserved coring was 34%higher than that obtained through open sampling methods.展开更多
Rice is a poor source of folate,an essential micronutrient for the body.Biofortification offers an effective way to enhance the folate content of rice and alleviate folate deficiencies in humans.In this study,we confi...Rice is a poor source of folate,an essential micronutrient for the body.Biofortification offers an effective way to enhance the folate content of rice and alleviate folate deficiencies in humans.In this study,we confirmed that OsADCS and OsGTPCHI,encoding the initial enzymes necessary for folate synthesis,positively regulate folate accumulation in knockout mutants of both japonica and indica rice backgrounds.The folate content in the low-folate japonica variety was slightly increased by the expression of the indica alleles driven by the endosperm-specific promoter.We further obtained co-expression lines by stacking OsADCS and OsGTPCHI genes;the folate accumulation in brown rice and polished rice reached 5.65μg/g and 2.95μg/g,respectively,representing 37.9-fold and 26.5-fold increases compared with the wild type.Transcriptomic analysis of rice grains from six transgenic lines showed that folate changes affected biological pathways involved in the synthesis and metabolism of rice seed storage substances,while the expression of other folate synthesis genes was weakly regulated.In addition,we identified Aus rice as a high-folate germplasm carrying superior haplotypes of OsADCS and OsGTPCHI through natural variation.This study provides an alternative and effective complementary strategy for rice biofortification,promoting the rational combination of metabolic engineering and conventional breeding to breed high-folate varieties.展开更多
A 56-day feeding trial was performed to evaluate the effects of dietary probiotic Clostridium butyricum(CB) on intestine digestive and metabolic capacities, intestine short-chain fatty acids(SCFA) content and body com...A 56-day feeding trial was performed to evaluate the effects of dietary probiotic Clostridium butyricum(CB) on intestine digestive and metabolic capacities, intestine short-chain fatty acids(SCFA) content and body composition of kuruma shrimp Marsupenaeus japonicus. Shrimp s were randomly allocated into 9 tanks, 30 each, and f ed with diets containing different levels of C. butyricum(1×10~9 cfug^(-1)): 0 mgg^(-1) feed(Control), 100 mgg^(-1) feed(CB-100), 200 mgg^(-1) feed(CB-200), while each level was triplicated. The results indicated that compared with the control group, the intestine pepsin(Pep) activity and 5-hydroxytryptamine(5-HT) concentration of two C. butyricum group s were both increased. Amylase(AM Y) and lipase(LPS) activities wer e only induced in CB-200 group. Alanine aminotransferase(ALT) and aspartate aminotransferase(A ST) activities of two C. butyricum group s showed no significant change. The α-amylase(AM Y) gene expression was induced in CB-200 group, and tryp sin gene expression of two C. butyricum treated group s were both induced. Intestine SCFA content and body composition analysis showed that the contents of propionic acid, butyric acid and the crude protein of two C. butyricum group s were all higher than those of control. These results revealed that C. butyricum can modulate intestine digestive and metabolic capacities, improve intestine SCFA content and body crude protein content in M. japonicus.展开更多
Phaeodactylum tricornutum is a potential livestock for the combined production of eicosapentaenoic acid(EPA) and fucoxanthin. In this study, six marine diatom strains identified as P. tricornutum were cultured and the...Phaeodactylum tricornutum is a potential livestock for the combined production of eicosapentaenoic acid(EPA) and fucoxanthin. In this study, six marine diatom strains identified as P. tricornutum were cultured and their total lipid, fatty acid composition and major photosynthetic pigments determined. It was found that the cell dry weight concentration and mean growth rate ranged between 0.24–0.36 g/L and 0.31–0.33/d, respectively. Among the strains, SCSIO771 presented the highest total lipid content, followed by SCSIO828, and the prominent fatty acids in all strains were C16:0, C16:1, C18:1, and C20:5(EPA). Polyunsaturated fatty acids, including C16:2, C18:2, and EPA, comprised a significant proportion of the total fatty acids. EPA was markedly high in all strains, with the highest in SCSIO828 at 25.65% of total fatty acids. Fucoxanthin was the most abundant pigment in all strains, with the highest in SCSIO828 as well, at 5.50 mg/g. The collective results suggested that strain SCSIO828 could be considered a good candidate for the concurrent production of EPA and fucoxanthin.展开更多
Carbon can change the phase components of low-density steels and influence the mechanical properties.In this study,a new method to control the carbon content and avoid the formation ofδ-ferrite by decarburization tre...Carbon can change the phase components of low-density steels and influence the mechanical properties.In this study,a new method to control the carbon content and avoid the formation ofδ-ferrite by decarburization treatment was proposed.The microstructural changes and mechanical characteristics with carbon content induced by decarburization were systematically examined.Crussard-Jaoul(C-J)analysis was employed to examine the work hardening characteristics during the tensile test.During decarburization by heat treatments,the carbon content within the austenite phase decreased,while Mn and Al were almost unchanged;this made the steel with full austenite transform into the austenite and ferrite dual phase.Meanwhile,(Ti,V)C carbides existed in both matrix phase and the mole fraction almost the same.In addition,the formation of other carbides restrained.Carbon loss induced a decrease in strength due to the weakening of the carbon solid solution.For the steel with the single austinite,the deformation mode of austenite was the dislocation planar glide,resulting in the formation of microbands.For the dual-phase steel,the deformation occurred by the dislocation planar glide of austenite first,with the increase in strain,the cross slip of ferrite took place,forming dislocation cells in ferrite.At the late stage of deformation,the work hardening of austinite increased rapidly,while that of ferrite increased slightly.展开更多
基金supported by the National Natural Science Foundation of China(30671270)the National 863 Program of China(2006AA 10Z1E9)the Project for Improved Variety of Shandong Provice,China(Lu Nong Liang Zhong Zi[2006]No.6).
文摘The protein content and amino acid composition for 17 wheat-related species （WRS） and three common wheats （control） were determined and analyzed, and the essential amino acids （EAAs） in WRS were evaluated according to FAO/WHO amino acid recommendations. The results showed that the mean protein content for WRS was 16.67%, which was 23.21% higher than that for the control. The mean contents （g 100 g^-1 protein） of most amino acids for WRS were lysine 2.74%, threonine 2.83%, phenylalanine 4.17%, isoleucine 3.42%, valine 3.90%, histidine 2.81%, glutamic acid 29.96%, proline 9.12%, glycine 3.59%, alanine 3.37%, and cysteine 1.57%, which were higher than those for the control. The contents of the other 6 amino acids for WRS were lower than those for the control. The materials （Triticum monococcum L., Triticum carthlicum Nevski, and Triticum turgidum L.） contained relatively high concentration of the most deficient EAAs （lysine, threonine, and methionine）. Comparing with FAO/WHO amino acid recommendations, the amino acid scores （AAS） of lysine （49.8%）, threonine （70.7%）, and sulfur-containing amino acids （74.8%） were the lowest, which were considered as the main limiting amino acids in WRS. It was observed that the materials with Triticum urartu Turn. （AA） and Aegilops speltoides Tausch. （SS） genomes had relatively high contents of protein and EAA. The contents of protein （16.91%）, phenylalanine （4.78%）, isoleucine （3.53%）, leucine （6.16%）, and valine （4.09%） for the diploid materials were higher than those for the other materials. These results will provide some information for selecting parents in breeding about nutrient quality and utilization of fine gene in wheat.
基金supported by National Science Foundation of China (Nos. 41172001 and 41772015 to Sun and No. 41772359 to Shen)
文摘Iron and manganese are the important redoxsensitive elements in the ocean. Previous studies have established a series of paleo-depositional redox proxies based on the form and content of iron in sedimentary rocks(e.g., degree of pyritization, FeHR/FeT, Fe/Al). These proxies were developed and applied on siliciclastic-rich marine sediments. Although marine carbonate rocks are generally considered to preserve the geochemical signals of ancient seawater, neither Fe nor Mn content in marine carbonate rocks(Fecarb, Mncarb) has been independently used as a proxy to quantify environmental cues in paleo-oceans. Both Fe and Mn are insoluble in oxic conditions(Fe_2O_3, Fe(OH)_3,MnO_2), while their reduced forms(Fe^(2+) and Mn^(2+)) are soluble. Therefore, oxic seawater should have low concentrations of dissolved Fe^(2+)and Mn^(2+), and accordingly carbonate rocks precipitated from oxic seawater should have low Fecarband Mncarb, and vice versa. To evaluate whether Fecarband Mncarbcan be used to quantify oxygen fugacity in seawater, we measured Fecarband Mncarbof Upper Devonian marine carbonate rocks collected from nine sections in South China. Fecarbof intraplatform basin samples wassignificantly higher than that of shelf samples, while shelf and basin samples had comparable Mncarb. The modeling result indicates that the dramatic difference in Fecarbcannot be explained by variation in oxygen fugacity between the shelf and basin seawater. Instead, both Fecarband Mncarb appear to be more sensitive to benthic flux from sediment porewater that is enriched in Fe^(2+)and Mn^(2+). Porewater Fe^(2+)and Mn^(2+)derive from bacterial iron and manganese reduction; flux was controlled by sedimentation rate and the depth of the Fe(Mn) reduction zone in sediments, the latter of which is determined by oxygen fugacity at the water–sediment interface. Thus, high Fecarbof the basin samples might be attributed to low sedimentation rate and/or low oxygen fugacity at the seafloor. However, invariant Mncarbof the shelf and basin samples might be the consequence of complete reduction of Mn in sediments. Our study indicates that marine carbonate rocks may not necessarily record seawater composition, particularly for benthic carbonate rocks. The influence of benthic flux might cause carbonate rocks' geochemical signals to deviate significantly from seawater values. Our study suggests that interpretation of geochemical data from carbonate rocks, including carbonate carbon isotopes, should consider the process of carbonate formation.
基金support of the Key Deployment Project of the Chinese Academy of Sciences (KZZD-EW-05-01)the National Natural Science Foundation of China(41472272,41102194)+1 种基金the Opening fund of State Key Laboratory of Geohazard Prevention and Geoenvironment Protection(Chengdu University of Technology)(SKLGP2013K015)the Science Foundation for Excellent Youth Scholars of Sichuan University(2013SCU04A07)
文摘Abundant landslide deposits were triggered by the Wenchuan earthquake, providing a rich source of material for subsequent debris flows or slope failures under rainfall conditions. A good understanding of the physical and mechanical properties of the landslide deposits is very important to the research on slope failure mechanisms and the initiation of debris flow. Laboratory biaxial compression tests are used to study the material compositions and water content impacts on the mechanical properties of landslide deposits, and a discrete element method （a bond-contact model） is used to study the particle stiffness, bond force, friction coefficient and confining stress impact on the mechanical behaviors and the relationships between the numerical and experimental parameters. The experimental results show that the failure stress of landslide deposits is decreased with increasing content of fine particles and also with increased water content, especially at the initial increasing stage. Cohesion of the saturated landslide deposits is increased, but the friction angle is decreased with the increase in the fine particle content. Shear strength parameters （the cohesion and friction angle） are decreased with the increasing water content at the initial increasing stage, and then, they slowly decrease. There is a critical value of the water content at 5%-7% （in weight） for the failure stress and shear strength parameters of the landslide deposits. Quadratic equations are presented to describe the relation between the bond force and cohesion, and the numerical friction coefficient and the experimental friction angle.
基金National Natural Science Foundation of China(U22A20191)。
文摘Brazing filler metals are widely applied,which serve as an industrial adhesive in the joining of dissimilar structures.With the continuous emergence of new structures and materials,the demand for novel brazing filler metals is ever-increasing.It is of great significance to investigate the optimized composition design methods and to establish systematic design guidelines for brazing filler metals.This study elucidated the fundamental rules for the composition design of brazing filler metals from a three-dimensional perspective encompassing the basic properties of applied brazing filler metals,formability and processability,and overall cost.The basic properties of brazing filler metals refer to their mechanical properties,physicochemical properties,electromagnetic properties,corrosion resistance,and the wettability and fluidity during brazing.The formability and processability of brazing filler metals include the processes of smelting and casting,extrusion,rolling,drawing and ring-making,as well as the processes of granulation,powder production,and the molding of amorphous and microcrystalline structures.The cost of brazing filler metals corresponds to the sum of materials value and manufacturing cost.Improving the comprehensive properties of brazing filler metals requires a comprehensive and systematic consideration of design indicators.Highlighting the unique characteristics of brazing filler metals should focus on relevant technical indicators.Binary or ternary eutectic structures can effectively enhance the flow spreading ability of brazing filler metals,and solid solution structures contribute to the formability.By employing the proposed design guidelines,typical Ag based,Cu based,Zn based brazing filler metals,and Sn based solders were designed and successfully applied in major scientific and engineering projects.
基金The Agricultural Seed Project of Shandong Province
文摘Sea cucumber, Apostichopus japonicus（Selenka）, is a commercially important marine species in China. Among the differently colored varieties sold in China, white and purple sea cucumbers have the greatest appeal to consumers. Identification of the pigments that may contribute to the formation of different color morphs of sea cucumbers will provide a scientific basis for improving the cultivability of desirable color morphs. In this study,sea cucumbers were divided into four categories according to their body color： white, light green, dark green, and purple. The pigment composition and contents in the four groups were analyzed by high performance liquid chromatography（HPLC）. The results show that the pigment contents differed significantly among the white, lightgreen, dark-green, and purple sea cucumbers, and there were fewer types of pigments in white sea cucumber than in the other color morphs. The only pigments detected in white sea cucumbers were guanine and pteroic acid.Guanine and pteroic acid are structural colors, and they were also detected in light-green, dark-green, and purple sea cucumbers. Every pigment detected, except for pteroic acid, was present at a higher concentration in purple morphs than in the other color morphs. The biological color pigments melanin, astaxanthin, β-carotene, and lutein were detected in light-green, dark-green, and purple sea cucumbers. While progesterone and lycopene,which are also biological color pigments, were not detected in any of the color morphs. Melanin was the major pigment contributing to body color, and its concentration increased with deepening color of the sea cucumber body. Transmission electron microscopy analyses revealed that white sea cucumbers had the fewest epidermal melanocytes in the body wall, and their melanocytes contained fewer melanosomes as well as non-pigmented pre-melanosomes. Sea cucumbers with deeper body colors contained more melanin granules. In the body wall of dark-green and purple sea cucumbers, melanin granules were secreted out of the cell. The results of this study provide evidence for the main factors responsible for differences in coloration among white, light-green, darkgreen, and purple sea cucumbers, and also provide the foundation for further research on the formation of body color in sea cucumber, A. japonicus.
文摘Twenty-nine japonica rice varieties collected from Jiangsu and Zhejiang Provinces, China were planted in Hangzhou, China, to investigate the phytic acid content in brown rice and its frequency distribution as well as the correlation among the contents of phytic acid, total protein and four protein compositions in brown rice. The phytic acid content in brown rice ranged from 0.699% to 1.034%, with a mean of 0.868% for the 29 tested rice varieties. Xiushui series rice varieties generally exhibited lower phytic acid level than Wuyujing and Huai series rice varieties. A rough normal distribution, with a mean of 8.722%, was observed for the total protein contents in the tested varieties. Of the four protein compositions, the glutelin, globulin and albumin contents had larger coefficient of variation than the prolamin content, although the difference in prolamin content was genotype-dependent. No significant correlation was found between the phytic acid and four protein composition contents, whereas the total protein content was significantly and positively related to the glutelin content in brown rice.
基金This work is supported by the National Natural Science Foundation of China （Grant Nos. 60336010 ＆ 90401001）973 Program （Grant No. TG 2000036603）the Student Innovation Program of CAS （No. 1731000500010）.
文摘It is important to acquire the composition of Si1-xGex layer, especially that with high Ge content, epitaxied on Si substrate. Two nondestructive examination methods, double crystals X-ray diffraction （DCXRD） and micro-Raman measurement, were introduced comparatively to determine x value in Si1-xGex layer, which show that while the two methods are consistent with each other when x is low, the results obtained from double crystals X-ray diffraction are not credible due to the large strain relaxation occurring in Si1-xGex layers when Ge content is higher than about 20%. Micro-Raman measurement is more appropriate for determining high Ge content than DCXRD.
文摘This study has been conducted to evaluate the influence of flux composition on the microstructure and oxygen content of the low carbon steel weldments using developed agglomerated fluxes.Ca_F2,FeMn and NiO were added to the CaO-SiO_2-Al_2O_3 base fluxes in the varying amount of 2%-8% to examine the various elements transferred to the weldments.The microstructure obtained was a mixture of pearlite and ferrite contents.This study reveals that CaF_2 and Fe Mn both are having significant effect on pearlite percentage while CaF_2 and NiO are significant for oxygen transfer in the welds.The interaction effects of CaF_2 and Fe Mn and CaF_2 and Ni O are also significant to the microstructure of the welds.The fluxes were designed using response surface methodology( RSM) and were developed by agglomeration technique.
文摘Fatty acids are the main constituents of vegetable oils.To determine the fatty acid compositions of small trade vegetable oils and some less well studied beneficial vegetable oils,and investigate their relationships with antioxidant activity and oxidative stability,gas chromatography-mass spectrometry was performed to characterize the associated fatty acid profiles.The antioxidant activity of vegetable oils,based on their DPPH-scavenging capacity(expressed as IC_(50) values),was used to assess their impact on human health,and their oxidative stability was characterized by performing lipid oxidation analysis to determine the oxidative induction time of fats and oils.In addition,correlation analyses were performed to examine associations between the fatty acid composition of the oils and DPPH-scavenging capacity and oxidative stability.The results revealed that among the assessed oils,coffee seed oil has the highest saturated fatty acid content(355.10 mg/g),whereas Garddenia jaminoides oil has the highest unsaturated fatty acid content(844.84 mg/g).Coffee seed oil was also found have the lowest DPPH IC_(50) value(2.30 mg/mL)and the longest oxidation induction time(17.09 h).Correlation analysis revealed a significant linear relationship(P<0.05)between oxidative stability and unsaturated fatty acid content,with lower contents tending to be associated with better oxidative stability.The findings of this study provide reference data for the screening of functional edible vegetable oils.
基金supported by the National Natural Science Foundation of China(Nos.51925103,52271149,52171159)the Innovation Program of Shanghai Municipal Education Commission(No.2021-01-07-00-09-E00114)+5 种基金the Natural Science Foundation of Shanghai(22ZR1422500)the Innovation Program of Shanghai Science and Technology(No.23520760700)the Aviation Foundation(No.2023Z0530S6004)the Fund of the State Key Laboratory of Solidification Processing in NWPU(No.SKLSP202221)the financial support from Program 173(No.2020-JCIQ-ZD-186-01)the Space Utilization System of China Manned Space Engineering(No.KJZ-YY-NCL08).
文摘Lightweight high/medium-entropy alloys(H/MEAs)possess attractive properties such as high strength-to-weight ratios,however,their limited room-temperature tensile ductility hinders their widespread engi-neering implementation,for instance in aerospace structural components.This work achieved a transfor-mative improvement of room-temperature tensile ductility in Ti-V-Zr-Nb MEAs with densities of 5.4-6.5 g/cm3,via ingenious composition modulation.Through the systematic co-adjustment of Ti and V contents,an intrinsic ductility mechanism was unveiled,manifested by a transition from predominant intergranular brittle fracture to pervasive ductile dimpled rupture.Notably,the modulated deformation mechanisms evolved from solitary slip toward collaborative multiple slip modes,without significantly compromising strength.Compared to equimolar Ti-V-Zr-Nb,a(Ti1.5V)3ZrNb composition demonstrated an impressive 360%improvement in elongation while sustaining a high yield strength of around 800 MPa.Increasing Ti and V not only purified the grain boundaries by reducing detrimental phases,but also tai-lored the deformation dislocation configurations.These insights expanded the applicability of lightweight HEAs to areas demanding combined high strength and ductility.
文摘Aseries of [(Fe_(0.6)Co_(0.2)Ni_(0.2))_(0.75-0.03x)B_(0.2)Si_(0.05+0.03x)]_(96)Nb_(4) amorphous alloy composite coatings were prepared by adjusting the silicon content(x=0,1,2,3,4,5,and 6)and their microstructures and tribological properties were investigated by laser cladding technique.Additionally,the effect of Si on the glass forming ability(GFA)of the layers was understood.Results show that an appropriate Si content can refine the microstructure of the FeCoNiBSiNb laser cladding layers and improve the mechanical and tribological properties.The hardness of the coating layer increases monotonically with the Si content.At the Si content of 4.8at%(x=0),the coating layer exhibits a relatively low hardness(734.2HV 0.1).Conversely,at the silicon content of 13.44at%(x=3),the coating layer exhibits the highest hardness(1106HV 0.1).The non-crystalline content and tensile strength exhibit an initial increase,followed by a subsequent decrease.At x=2,the coating exhibits its maximum fracture strength(2880 MPa).However,when x>2,the fracture strength of the coating decreases with an increase in x.Conversely,with an increase in Si content,the wear volume loss initially decreases and then increases.At a Si content of 10.56at%(x=2),the coating exhibits the highest non-crystalline content(42%),the highest tensile strength(2880 MPa),and the most favorable dry friction performance.
文摘In order to adjust some properties of cement grout or concrete,some mineral admixtures are usually added in the preparation.Admixtures can reduce the cement consumption and save the cost,and also adjust the workability of the material,improve the strength and durability of the cement stone,or reduce hydration heat of the composite cement.At present,the content of fly ash or slag is generally less than 50%among the composite cementitious materials that have been studied more,but there is little research on composite cementitious materials with large mineral admixture.In this paper,XRD,SEM,and adiabatic temperature rise tests were used to discuss hydration products and mechanism of composite cement grout with 90%content of fly ash and slag.The results show that the hydration of the composite cement grout is an alkali-activated hydration reaction,and the hydration products are mainly amorphous substances such as hydrated calcium silicate or hydrated calcium aluminate gel.The hydration reaction temperature rise is much lower than that of ordinary cement grout,and the time of the temperature peak is significantly delayed.
基金supported by the Surface Project of Local De-velopment in Science and Technology Guided by Central Govern-ment(No.2021ZYD0041)the National Natural Science Founda-tion of China(Nos.52377026 and 52301192)+3 种基金the Natural Science Foundation of Shandong Province(No.ZR2019YQ24)the Taishan Scholars and Young Experts Program of Shandong Province(No.tsqn202103057)the Special Financial of Shandong Province(Struc-tural Design of High-efficiency Electromagnetic Wave-absorbing Composite Materials and Construction of Shandong Provincial Tal-ent Teams)the“Sanqin Scholars”Innovation Teams Project of Shaanxi Province(Clean Energy Materials and High-Performance Devices Innovation Team of Shaanxi Dongling Smelting Co.,Ltd.).
文摘With the increasing complexity of the current electromagnetic environment,excessive microwave radi-ation not only does harm to human health but also forms various electromagnetic interference to so-phisticated electronic instruments.Therefore,the design and preparation of electromagnetic absorbing composites represent an efficient approach to mitigate the current hazards of electromagnetic radiation.However,traditional electromagnetic absorbers are difficult to satisfy the demands of actual utilization in the face of new challenges,and emerging absorbents have garnered increasing attention due to their structure and performance-based advantages.In this review,several emerging composites of Mxene-based,biochar-based,chiral,and heat-resisting are discussed in detail,including their synthetic strategy,structural superiority and regulation method,and final optimization of electromagnetic absorption ca-pacity.These insights provide a comprehensive reference for the future development of new-generation electromagnetic-wave absorption composites.Moreover,the potential development directions of these emerging absorbers have been proposed as well.
文摘The aim of this work was to contribute to our knowledge of the proximate composition, mineral and vitamin content of 20 edible wild plants used as spices in Cameroon. The plant species were collected from 3 different markets in the West Region of Cameroon and analysed for their content of crude proteins, and lipid, ash, moisture, available sugars, total phenols, carotenoids, minerals (Ca, Zn, K, Na, Mg, Al, Mn, Cu and Se), and vitamins (A, E and C) as well as for their pH and colour. Results revealed that all the plants were low in moisture (7.7 to 10.5 g/100 g) but high in ash content (7.7 to 10.5 g/100 g). Hua gabonii (bark) (1594.5 mg/100 g) was relative source of calcium, Echinops giganteus (206.4 mg/100 g) exhibited the highest level of iron and Scorodophleus zenkeri (310.0 μg/100 g) the highest level of selenium. Generally all the plants were found to contain low levels of Zn, Cu and Mg. Wide variations were observed for the pro- teins and available sugars among the samples. The lipid content of some of the plants were surprisingly relatively high as was the case with Monodora myristica (53.4 g/100 g), Xylopia aethiopica (33.7 g/100 g), Fagara leprieuri (32.1 g/100 g), and Aframomum daniellii (23.1 g/100 g). All the plants were rich in phenols, carotenoids, vitamin E and C. They are dark in colour and in solution they tended to provoke a fair acidification.
文摘To obtain solid Al2O3 or MgO·Al2O3 inclusions in ladle furnace(LF)refining process and achieve ultra-low total oxygen content in steel through subsequent Ruhrstahl Heraeus degassing,the effects of ferrosilicon alloy,Si content of steel,and slag basicity on the compositions of inclusions during LF refining were investigated in Al-killed steel.Al2O3 inclusions could be transformed into CaO-Al2O3-MgO-CaS inclusions after adding ferrosilicon alloy in the LF refining process as this alloy contains some CaSi alloy impurities.The addition of all ferrosilicon alloys required for the steel in the tapping process could eliminate the influence of Ca in ferrosilicon alloy on the compositions of inclusions.Si in liquid steel had a significant influence on the compositions of inclusions during LF refining when CaO-Al2O3-SiO2-MgO slag with high basicity of 7.0 was used.This was because[Ca]produced by the reaction of CaO and[Al]could be consumed more readily by SiO2 in Si-free steel than in Si-containing steel,which was confirmed by the difference of total calcium content between Si-free and Si-containing steels.As a result,Al2O3 and MgO·Al2O3 inclusions were retained in Si-free steel,whereas calcium aluminate inclusions were found in Si-containing steel.For CaO-Al2O3-SiO2-MgO slag with low basicity of 2.8,Al2O3 and MgO·Al2O3 inclusions were obtained after LF refining in Si-containing steel when all ferrosilicon alloys required for the steel were added in the tapping process.This was because the reaction of CaO and[Al]was weak,and residual[Ca]in the steel could be rapidly consumed by SiO2 in low-basicity slag owing to the low activity of CaO and high activity of SiO2,leading to a low total calcium content of 0.0003%in Si-containing steel.
基金supported by the National Natural Science Foundation of China(Nos.51827901,42477191,and 52304033)the Fundamental Research Funds for the Central Universities(No.YJ202449)+1 种基金the Open Research Fund of State Key Laboratory of Geomechanics and Geotechnical Engineering,Institute of Rock and Soil Mechanics,Chinese Academy of Sciences(No.SKLGME022009)the China Postdoctoral Science Foundation(No.2023M742446).
文摘Gas content serves as a critical indicator for assessing the resource potential of deep coal mines and forecasting coal mine gas outburst risks.However,existing sampling technologies face challenges in maintaining the integrity of gas content within samples and are often constrained by estimation errors inherent in empirical formulas,which results in inaccurate gas content measurements.This study introduces a lightweight,in-situ pressure-and gas-preserved corer designed to collect coal samples under the pressure conditions at the sampling point,effectively preventing gas loss during transfer and significantly improving measurement accuracy.Additionally,a gas migration model for deep coal mines was developed to elucidate gas migration characteristics under pressure-preserved coring conditions.The model offers valuable insights for optimizing coring parameters,demonstrating that both minimizing the coring hole diameter and reducing the pressure difference between the coring-point pressure and the original pore pressure can effectively improve the precision of gas content measurements.Coring tests conducted at an experimental base validated the performance of the corer and its effectiveness in sample collection.Furthermore,successful horizontal coring tests conducted in an underground coal mine roadway demonstrated that the measured gas content using pressure-preserved coring was 34%higher than that obtained through open sampling methods.
基金supported by the Central Public-Interest Scientific Institution Basal Research Fund,China(Grant No.CPSIBRF-CNRRI-202403)。
文摘Rice is a poor source of folate,an essential micronutrient for the body.Biofortification offers an effective way to enhance the folate content of rice and alleviate folate deficiencies in humans.In this study,we confirmed that OsADCS and OsGTPCHI,encoding the initial enzymes necessary for folate synthesis,positively regulate folate accumulation in knockout mutants of both japonica and indica rice backgrounds.The folate content in the low-folate japonica variety was slightly increased by the expression of the indica alleles driven by the endosperm-specific promoter.We further obtained co-expression lines by stacking OsADCS and OsGTPCHI genes;the folate accumulation in brown rice and polished rice reached 5.65μg/g and 2.95μg/g,respectively,representing 37.9-fold and 26.5-fold increases compared with the wild type.Transcriptomic analysis of rice grains from six transgenic lines showed that folate changes affected biological pathways involved in the synthesis and metabolism of rice seed storage substances,while the expression of other folate synthesis genes was weakly regulated.In addition,we identified Aus rice as a high-folate germplasm carrying superior haplotypes of OsADCS and OsGTPCHI through natural variation.This study provides an alternative and effective complementary strategy for rice biofortification,promoting the rational combination of metabolic engineering and conventional breeding to breed high-folate varieties.
基金supported by Guangdong Provincial Special Fund for Marine Fisheries Technology (No. A 201701B09)Fund of Key Laboratory of South China Sea Fishery Resources Exploitation & Utilization, Ministry of Agriculture, P. R. China (No. FREU2017-01)+4 种基金Guangdong Natural Science Foundation (No. 2017A 030 313147)Special Scientific Research Funds for Central Public-interest Scientific Institution Basal Research Fund, South China Sea Fisheries Research Institute, CAFS (Nos. 2016TS07, 2017YB12)Guangdong Provincial Key Laboratory of Fishery Ecology and Environment (No. LFE2016-12)the National Natural Science Foundation of China (Nos. 31502183, 31702352)Shenzhen Science and Technology Planning Project (No. JCYJ201704 12110605075)
文摘A 56-day feeding trial was performed to evaluate the effects of dietary probiotic Clostridium butyricum(CB) on intestine digestive and metabolic capacities, intestine short-chain fatty acids(SCFA) content and body composition of kuruma shrimp Marsupenaeus japonicus. Shrimp s were randomly allocated into 9 tanks, 30 each, and f ed with diets containing different levels of C. butyricum(1×10~9 cfug^(-1)): 0 mgg^(-1) feed(Control), 100 mgg^(-1) feed(CB-100), 200 mgg^(-1) feed(CB-200), while each level was triplicated. The results indicated that compared with the control group, the intestine pepsin(Pep) activity and 5-hydroxytryptamine(5-HT) concentration of two C. butyricum group s were both increased. Amylase(AM Y) and lipase(LPS) activities wer e only induced in CB-200 group. Alanine aminotransferase(ALT) and aspartate aminotransferase(A ST) activities of two C. butyricum group s showed no significant change. The α-amylase(AM Y) gene expression was induced in CB-200 group, and tryp sin gene expression of two C. butyricum treated group s were both induced. Intestine SCFA content and body composition analysis showed that the contents of propionic acid, butyric acid and the crude protein of two C. butyricum group s were all higher than those of control. These results revealed that C. butyricum can modulate intestine digestive and metabolic capacities, improve intestine SCFA content and body crude protein content in M. japonicus.
基金Supported by the Knowledge Innovation Program of Chinese Academy of Sciences(No.SQ201213)the National Natural Science Foundation of China(No.31402320)+1 种基金the Guangdong Province and Chinese Academy of Science Cooperation Foundation(No.2012B091100268)the Technology Project of Ocean and Fisheries of Guangdong Province(No.A201101I04)
文摘Phaeodactylum tricornutum is a potential livestock for the combined production of eicosapentaenoic acid(EPA) and fucoxanthin. In this study, six marine diatom strains identified as P. tricornutum were cultured and their total lipid, fatty acid composition and major photosynthetic pigments determined. It was found that the cell dry weight concentration and mean growth rate ranged between 0.24–0.36 g/L and 0.31–0.33/d, respectively. Among the strains, SCSIO771 presented the highest total lipid content, followed by SCSIO828, and the prominent fatty acids in all strains were C16:0, C16:1, C18:1, and C20:5(EPA). Polyunsaturated fatty acids, including C16:2, C18:2, and EPA, comprised a significant proportion of the total fatty acids. EPA was markedly high in all strains, with the highest in SCSIO828 at 25.65% of total fatty acids. Fucoxanthin was the most abundant pigment in all strains, with the highest in SCSIO828 as well, at 5.50 mg/g. The collective results suggested that strain SCSIO828 could be considered a good candidate for the concurrent production of EPA and fucoxanthin.
基金financially supported by the National Natural Science Foundation of China(Nos.U2141207,52171111,and 52001083)the Youth Talent Project of China National Nuclear Corporation(No.CNNC2021Y-TEPHEU01)+3 种基金the China Postdoctoral Science Foundation(No.2020M681077)the Natural Science Foundation of Heilongjiang,China(No.LH2019E030)the Heilongjiang Postdoctoral Science Foundation,China(No.LBH-Z19125)he Heilongjiang Touyan Innovation Team Program,China,and the Natural Science Foundation of Heilongjiang(No.LH2020E060)。
文摘Carbon can change the phase components of low-density steels and influence the mechanical properties.In this study,a new method to control the carbon content and avoid the formation ofδ-ferrite by decarburization treatment was proposed.The microstructural changes and mechanical characteristics with carbon content induced by decarburization were systematically examined.Crussard-Jaoul(C-J)analysis was employed to examine the work hardening characteristics during the tensile test.During decarburization by heat treatments,the carbon content within the austenite phase decreased,while Mn and Al were almost unchanged;this made the steel with full austenite transform into the austenite and ferrite dual phase.Meanwhile,(Ti,V)C carbides existed in both matrix phase and the mole fraction almost the same.In addition,the formation of other carbides restrained.Carbon loss induced a decrease in strength due to the weakening of the carbon solid solution.For the steel with the single austinite,the deformation mode of austenite was the dislocation planar glide,resulting in the formation of microbands.For the dual-phase steel,the deformation occurred by the dislocation planar glide of austenite first,with the increase in strain,the cross slip of ferrite took place,forming dislocation cells in ferrite.At the late stage of deformation,the work hardening of austinite increased rapidly,while that of ferrite increased slightly.
