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Oils with different degree of saturation:effects on ileal digestibility of fat and corresponding additivity and bacterial community in growing pigs
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作者 Lu Wang Yifan Chen +2 位作者 Yuansen Yang Nuo Xiao Changhua Lai 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第4期1657-1668,共12页
Background Oils are important sources of energy in pig diets.The combination of oils with different degree of saturation contributes to improve the utilization efficiency of the mixed oils and may reduce the cost of o... Background Oils are important sources of energy in pig diets.The combination of oils with different degree of saturation contributes to improve the utilization efficiency of the mixed oils and may reduce the cost of oil supplemented.An experiment was conducted to evaluate the effects of oils with different degree of saturation on the fat digestibility and corresponding additivity and bacterial community in growing pigs.Methods Eighteen crossbred(Duroc×Landrace×Yorkshire)barrows(initial body weight:29.3±2.8 kg)were surgically fitted with a T-cannula in the distal ileum.The experimental diets included a fat-free basal diet and 5 oil-added diets.The 5 oil-added diets were formulated by adding 6%oil with different ratio of unsaturated to saturated fatty acids(U:S)to the basal diet.The 5 oils were palm oil(U:S=1.2),canola oil(U:S=12.0),and palm oil and canola oil were mixed in different proportions to prepare a combination of U:S of 2.5,3.5 and 4.5,respectively.Results The apparent and standardized ileal digestibility(AID and SID)of fat and fatty acids increased linearly(P<0.05)as the U:S of dietary oils increased except for SID of fat and C18:2.The AID and SID of fat and fatty acids differed among the dietary treatments(P<0.05)except for SID of unsaturated fatty acids(UFA)and C18:2.Fitted one-slope broken-line analyses for the SID of fat,saturated fatty acids(SFA)and UFA indicated that the breakpoint for U:S of oil was 4.14(R^(2)=0.89,P<0.01),2.91(R^(2)=0.98,P<0.01)and 3.84(R^(2)=0.85,P<0.01),respectively.The determined SID of fat,C18:1,C18:2 and UFA in the mixtures was not different from the calculated SID of fat,C18:1,C18:2 and UFA.However,the determined SID of C16:0,C18:0 and SFA in the mixtures were greater than the calculated SID values(P<0.05).The abundance of Romboutsia and Turicibacter in pigs fed diet containing palm oil was greater than that in rapeseed oil treatment group,and the two bacteria were negatively correlated with SID of C16:0,C18:0 and SFA(P<0.05).Conclusions The optimal U:S for improving the utilization efficiency of mixed oil was 4.14.The SID of fat and UFA for palm oil and canola oil were additive in growing pigs,whereas the SID of SFA in the mixture of two oils was greater than the sum of the values of pure oils.Differences in fat digestibility caused by oils differing in degree of saturation has a significant impact on bacterial community in the foregut. 展开更多
关键词 additivity Bacterial community Fat and fatty acids Growing pigs Ratio of unsaturated to saturated fatty acids Standardized ileal digestibility
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Additivity rule for electron-molecule total cross section calculations at 50-5000 eV: a new geometrical approach
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作者 施德恒 孙金锋 +1 位作者 朱遵略 刘玉芳 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第6期2103-2109,共7页
Taking into consideration the changes of the geometric shielding effect in a molecule as the energy of incident electrons varies, this paper presents an empirical fraction, which depends on the energy of incident elec... Taking into consideration the changes of the geometric shielding effect in a molecule as the energy of incident electrons varies, this paper presents an empirical fraction, which depends on the energy of incident electrons, the target's molecular dimension and the atomic and electronic numbers in the molecule. Using this empirical fraction, it proposes a new formulation of the additivity rule. Employing the new additivity rule, it calculates the total cross sections of electron scattering by C2H4, C6H6, C6H14 and C8H18 over the energy range from 50 to 5000eV. In order to exclude the calculation deviations caused by solving the radial Schrodinger equation of electron scattering by atoms, here the atomic cross sections are derived from the experimental total cross section results of simple molecules (H2, O2, CO) via the inversion algorithm. The quantitative total cross sections are compared with those obtained by experiments and other theories, and good agreement is obtained over a wide energy range, even at energy of several tens of eV. 展开更多
关键词 electron scattering total cross section additivity rule geometric shielding effect
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Total cross sections for electron scattering from fluoromethanes:A revised additivity rule method
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作者 谭晓明 赵刚 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第6期167-171,共5页
The additivity rule for electron-molecule scattering is revised by considering the difference between the free atom and the bound atom in the molecule. The total cross sections for electron scattering from fluorometha... The additivity rule for electron-molecule scattering is revised by considering the difference between the free atom and the bound atom in the molecule. The total cross sections for electron scattering from fluoromethanes (CF4, CF3H, CF2H2, and CFH3) are calculated in an energy range from 100 eV to 1500 eV by the revised additivity rule. The present calculations are compared with the original additivity rule results and the available experimental data. Better agreement with each other is obtained. 展开更多
关键词 total cross section electron scattering revised additivity rule
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Comparison of methods for estimating basal endogenous losses of amino acids and additivity of digestibility of amino acids in corn and soybean meal for broilers
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作者 June Hyeok Yoon Changsu Kong 《Animal Nutrition》 SCIE CAS CSCD 2023年第4期233-241,共9页
This study was to compare the estimates of basal endogenous losses(BEL)of amino acids(AA)determined by 3 methods including feeding a nitrogen-free diet(NFD)or a low-casein diet(LCD,containing casein at 30 g/kg diet)or... This study was to compare the estimates of basal endogenous losses(BEL)of amino acids(AA)determined by 3 methods including feeding a nitrogen-free diet(NFD)or a low-casein diet(LCD,containing casein at 30 g/kg diet)or using the regression method.Another objective was to investigate whether the ileal AA digestibility of corn calculated from a casein-supplemented corn diet is additive for a cornsoybean meal(SBM)mixed diet in broilers.On d 31 of age,168 Ross 308 male broilers were assigned to 8 dietary treatments with 6 replicates in a randomized complete block design.An NFD and 3 diets containing 30,60,or 90 g/kg of casein were formulated to determine the BEL of AA and ileal AA digestibility of casein.The other 4 diets consisted of a corn diet,SBM diet,casein-supplemented corn diet,and corn-SBM mixed diet.On d 35 of age,digesta from the distal section of the ileum were collected.The BEL of AA in birds fed the LCD were greater(P<0.05)than those of the NFD and the regression method.There were no differences in the BEL of AA determined between the NFD and the regression method.Apparent ileal digestibility(AID)and standardized ileal digestibility(SID)of AA for corn calculated from the casein-supplemented corn diet were greater(P<0.05)than those of the corn diet.The predicted AID of Thr in the corn-SBM mixed diet based on the AID of AA for corn in the corn diet was lower(P<0.05)than the measured AID.However,the predicted AID of AA in the mixed diet based on the AID of AA for corn in the casein-supplemented corn diet did not differ from the measured AID.The predicted SID of AA in the mixed diet did not differ from the measured SID irrespective of casein supplementation.In conclusion,feeding an NFD or using the regression method yields similar BEL of AA,but not feeding an LCD.Casein supplementation in the corn diet increases the ileal AA digestibility for corn,which is additive for the corn-SBM mixed diet. 展开更多
关键词 Amino acid CASEIN Broiler additivity Basal endogenous loss
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Microstructure and thermal properties of dissimilar M300–CuCr1Zr alloys by multi-material laser-based powder bed fusion 被引量:1
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作者 Xiaoshuang Li Dmitry Sukhomlinov Zaiqing Que 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CSCD 2024年第1期118-128,共11页
Multi-material laser-based powder bed fusion (PBF-LB) allows manufacturing of parts with 3-dimensional gradient and additional functionality in a single step. This research focuses on the combination of thermally-cond... Multi-material laser-based powder bed fusion (PBF-LB) allows manufacturing of parts with 3-dimensional gradient and additional functionality in a single step. This research focuses on the combination of thermally-conductive CuCr1Zr with hard M300 tool steel.Two interface configurations of M300 on CuCr1Zr and CuCr1Zr on M300 were investigated. Ultra-fine grains form at the interface due to the low mutual solubility of Cu and steel. The material mixing zone size is dependent on the configurations and tunable in the range of0.1–0.3 mm by introducing a separate set of parameters for the interface layers. Microcracks and pores mainly occur in the transition zone.Regardless of these defects, the thermal diffusivity of bimetallic parts with 50vol% of CuCr1Zr significantly increases by 70%–150%compared to pure M300. The thermal diffusivity of CuCr1Zr and the hardness of M300 steel can be enhanced simultaneously by applying the aging heat treatment. 展开更多
关键词 multi-material additive manufacturing laser-based powder bed fusion thermal diffusivity dissimilar metals copper alloy
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Testing for additivity with B-splines 被引量:1
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作者 Heng-jian CUI, Xu-ming HE & Li LIU Department of Statistics and Financial Mathematics, School of Mathematical Sciences, Beijing Normal University, Beijing 100875, China Department of Statistics, University of Illinois, Champaign, IL 61820, USA National Institute of Statistical Science, Durham, NC 27709, USA 《Science China Mathematics》 SCIE 2007年第6期841-858,共18页
Regression splines are often used for fitting nonparametric functions, and they work especially well for additivity models. In this paper, we consider two simple tests of additivity: an adaptation of Tukey’s one degr... Regression splines are often used for fitting nonparametric functions, and they work especially well for additivity models. In this paper, we consider two simple tests of additivity: an adaptation of Tukey’s one degree of freedom test and a nonparametric version of Rao’s score test. While the Tukey-type test can detect most forms of the local non-additivity at the parametric rate of O(n-1/2), the score test is consistent for all alternative at a nonparametric rate. The asymptotic distribution of these test statistics is derived under both the null and local alternative hypotheses. A simulation study is conducted to compare their finite-sample performances with some existing kernel-based tests. The score test is found to have a good overall performance. 展开更多
关键词 additivity B-SPLINES DIMENSION reduction SCORE TEST SMOOTHING Tukey test.
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Novel uses of ensiled biomasses as feedstocks for green biorefineries
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作者 Marketta Rinne 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第3期945-955,共11页
Perennial forage plants are efficient utilizers of solar radiation and nutrients so that there is a lot of scope to increase the production of green biomass in many areas.Currently,grasses are mainly used as feeds for... Perennial forage plants are efficient utilizers of solar radiation and nutrients so that there is a lot of scope to increase the production of green biomass in many areas.Currently,grasses are mainly used as feeds for ruminants and equines,but there could be higher added value use for several components of the green biomass.Interest in green biorefin-ing has risen recently motivated by the increased sustainability pressures and need to break the reliance on fossil fuels.Novel products derived from grass,such as paper and packaging,nanofibers,animal bedding,novel protein feeds,extracted proteins,biochemicals,nutraceuticals,bioactive compounds,biogas and biochar could create new sustainable business opportunities in rural areas.Most green biorefinery concepts focus on using fresh green biomass as the feedstock,but preservation of it by ensiling would provide several benefits such as all-year-around avail-ability of the feedstock and increased stability of the press juice and press cake.The major difference between fresh and ensiled grass is the conversion of water soluble carbohydrates into fermentation end products,mainly lactic and acetic acids,that lower the pH of the silage so that it becomes stable in anaerobic conditions.This has some important consequences on the processability and quality of products,which are partly positive and partly negative,e.g.,degradation of protein into peptides,amino acids and ammonia.These aspects are discussed in this review. 展开更多
关键词 ADDITIVE FERMENTATION Liquid-solid separation Protein SILAGE
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The biological functions and metabolic pathways of valine in swine
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作者 Chuni Wang Yao Peng +4 位作者 Yiru Zhang Juan Xu Sheng Jiang Leli Wang Yulong Yin 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第1期20-34,共15页
Valine is an essential amino acid and a type of branched-chain amino acid. Due to the involvement of branchedchain amino acids in various metabolic pathways, there has been a surge of interests in valine nutrition and... Valine is an essential amino acid and a type of branched-chain amino acid. Due to the involvement of branchedchain amino acids in various metabolic pathways, there has been a surge of interests in valine nutrition and its role in animal physiology. In pigs, the interactions between valine and other branched-chain amino acids or aromatic amino acids are complex. In this review, we delve into the interaction mechanism, metabolic pathways, and biological functions of valine. Appropriate valine supplementation not only enhances growth and reproductive performances, but also modulates gut microbiota and immune functions. Based on past observations and interpretations, we provide recommended feed levels of valine for weaned piglets, growing pigs, gilts, lactating sows, barrows and entire males. The summarized valine nutrient requirements for pigs at different stages offer valuable insights for future research and practical applications in animal husbandry. 展开更多
关键词 Additional dosage Biological function Metabolic pathway PIG VALINE
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A multifunctional electrolyte additive for zinc-ion capacitors with low temperature resistant and long lifespan
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作者 Ming Sun Zekai Zhang +6 位作者 Shuqing Fu Yifan Zhang Ruoyu Wang Hongchun Mu Cheng Lian Wenqiang Wang Gengchao Wang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第7期477-485,共9页
Aqueous zinc-ion capacitors (ZICs) are considered as potential candidates for next generation electrochemical energy storage devices due to their high safety and low cost.However,the existing aqueous ZICs usually have... Aqueous zinc-ion capacitors (ZICs) are considered as potential candidates for next generation electrochemical energy storage devices due to their high safety and low cost.However,the existing aqueous ZICs usually have the problems of zinc dendrite growth and unsatisfactory performance at low temperature.Herein,an erythritol (Eryt) additive with inhibition of zinc dendrites and anti-freezing capability was introduced into the ZnSO4electrolyte.The experimental characterization and theoretical calculation confirm that the Eryt adsorbed on the surface of zinc anodes regulates the deposition orientation of Zn^(2+) and inhibits the formation of dendrites.It also reconstructs the solvation structure in the electrolyte to reduce water activity,enabling the electrolyte to have a lower freezing point for operation at low temperature.With the assistance of Eryt,the Zn||Zn symmetric cell exhibits a long cycle life of 2000 h,while the ZIC assembled with activated carbon (AC) cathode and zinc anode (Zn||AC) maintains a capacity retention of 98.2% after 30,000 cycles at a current density of 10 A g^(-1)(even after 10,000 cycles at-20°C,the capacity retention rate reached 94.8%.).This work provides a highly scalable,low-cost and effective strategy for the protection of the anodes of low-temperature aqueous ZICs. 展开更多
关键词 Zinc-ioncapacitors Electrolyte additive Dendrite-free Freeze-resistant electrolyte
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Evaluation of ruminal methane and ammonia formation and microbiota composition as affected by supplements based on mixtures of tannins and essential oils using Rusitec
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作者 Giulia Foggi Melissa Terranova +9 位作者 Matteo Daghio Sergej L.Amelchanka Giuseppe Conte Simon Ineichen Monica Agnolucci Carlo Viti Alberto Mantino Arianna Buccioni Michael Kreuzer Marcello Mele 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第4期1607-1622,共16页
Background Dietary supplements based on tannin extracts or essential oil compounds(EOC)have been repeatedly reported as a promising feeding strategy to reduce the environmental impact of ruminant husbandry.A previous ... Background Dietary supplements based on tannin extracts or essential oil compounds(EOC)have been repeatedly reported as a promising feeding strategy to reduce the environmental impact of ruminant husbandry.A previous batch culture screening of various supplements identified selected mixtures with an enhanced potential to mitigate ruminal methane and ammonia formation.Among these,Q-2(named after quebracho extract and EOC blend 2,composed of carvacrol,thymol,and eugenol)and C-10(chestnut extract and EOC blend 10,consisting of oregano and thyme essential oils and limonene)have been investigated in detail in the present study with the semi-continuous rumen simulation technique(Rusitec)in three independent runs.For this purpose,Q-2 and C-10,dosed according to the previous study,were compared with a non-supplemented diet(negative control,NC)and with one supplemented with the commercial EOC-based Agolin^(R) Ruminant(positive control,PC).Results From d 5 to 10 of fermentation incubation liquid was collected and analysed for pH,ammonia,protozoa count,and gas composition.Feed residues were collected for the determination of ruminal degradability.On d 10,samples of incubation liquid were also characterised for bacterial,archaeal and fungal communities by high-throughput sequencing of 16S rRNA and 26S ribosomal large subunit gene amplicons.Regardless of the duration of the fermentation period,Q-2 and C-10 were similarly efficient as PC in mitigating either ammonia(-37%by Q-2,-34%by PC)or methane formation(-12%by C-10,-12%by PC).The PC was also responsible for lower feed degradability and bacterial and fungal richness,whereas Q-2 and C-10 effects,particularly on microbiome diversities,were limited compared to NC.Conclusions All additives showed the potential to mitigate methane or ammonia formation,or both,in vitro over a period of 10 d.However,several differences occurred between PC and Q-2/C-10,indicating different mechanisms of action.The pronounced defaunation caused by PC and its suggested consequences apparently determined at least part of the mitigant effects.Although the depressive effect on NDF degradability caused by Q-2 and C-10 might partially explain their mitigation properties,their mechanisms of action remain mostly to be elucidated. 展开更多
关键词 Additive Bacteria Continuous culture DEGRADABILITY Fermentation Fungi Greenhouse gas In vitro Microbiome RUMEN
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Post processing of additive manufactured Mg alloys:Current status,challenges,and opportunities
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作者 Nooruddin Ansari Fatima Ghassan Alabtah +1 位作者 Mohammad I.Albakri Marwan Khraisheh 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第4期1283-1310,共28页
Magnesium(Mg)and its alloys are emerging as a structural material for the aerospace,automobile,and electronics industries,driven by the imperative of weight reduction.They are also drawing notable attention in the med... Magnesium(Mg)and its alloys are emerging as a structural material for the aerospace,automobile,and electronics industries,driven by the imperative of weight reduction.They are also drawing notable attention in the medical industries owing to their biodegradability and a lower elastic modulus comparable to bone.The ability to manufacture near-net shape products featuring intricate geometries has sparked huge interest in additive manufacturing(AM)of Mg alloys,reflecting a transformation in the manufacturing sectors.However,AM of Mg alloys presents more formidable challenges due to inherent properties,particularly susceptibility to oxidation,gas trapping,high thermal expansion coefficient,and low solidification temperature.This leads to defects such as porosity,lack of fusion,cracking,delamination,residual stresses,and inhomogeneity,ultimately influencing the mechanical,corrosion,and surface properties of AM Mg alloys.To address these issues,post-processing of AM Mg alloys are often needed to make them suitable for application.The present article reviews all post-processing techniques adapted for AM Mg alloys to date,including heat treatment,hot isostatic pressing,friction stir processing,and surface peening.The utilization of these methods within the hybrid AM process,employing interlayer post-processing,is also discussed.Optimal post-processing conditions are reported,and their influence on the microstructure,mechanical,and corrosion properties are detailed.Additionally,future prospects and research directions are proposed. 展开更多
关键词 Magnesium alloy Additive manufacturing POST-PROCESSING Heat treatment HIP
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Inclusion of CoTiO_(3) to ameliorate the re/dehydrogenation properties of the Mg–Na–Al system
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作者 N.A.Ali N.Y.Yusnizam +3 位作者 N.A.Sazelee Sami-ullah Rather Haizhen Liu M.Ismail 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第3期1215-1226,共12页
For the first time,the MgH_(2)–NaAlH_(4)(ratio 4:1)destabilized system with CoTiO_(3) addition has been explored.The CoTiO_(3)-doped MgH_(2)–NaAlH_(4) sample begins to dehydrogenate at 130℃,which is declined by 40... For the first time,the MgH_(2)–NaAlH_(4)(ratio 4:1)destabilized system with CoTiO_(3) addition has been explored.The CoTiO_(3)-doped MgH_(2)–NaAlH_(4) sample begins to dehydrogenate at 130℃,which is declined by 40℃ compared to the undoped MgH_(2)–NaAlH_(4).Moreover,the de/rehydrogenation kinetics characteristics of the CoTiO_(3)-doped MgH_(2)–NaAlH_(4) were greatly ameliorated.With the inclusion of CoTiO_(3),the MgH_(2)–NaAlH_(4) composite absorbed 5.2 wt.%H_(2),higher than undoped MgH_(2)–NaAlH_(4).In the context of dehydrogenation,the CoTiO_(3)-doped MgH_(2)–NaAlH_(4) sample desorbed 2.6 wt.%H_(2),almost doubled compared to the amount of hydrogen desorbed from the undoped MgH_(2)–NaAlH_(4) sample.The activation energy obtained by the Kissinger analysis for MgH_(2) decomposition was significantly lower by 35.9 kJ/mol than the undoped MgH_(2)–NaAlH_(4) sample.The reaction mechanism demonstrated that new phases of MgCo and AlTi_(3) were generated in situ during the heating process and are likely to play a substantial catalytic function and be useful in ameliorating the de/rehydrogenation properties of the destabilized MgH_(2)–NaAlH_(4) system with the inclusion of CoTiO_(3). 展开更多
关键词 Destabilize system Magnesium hydride Sodium alanate Hydrogen storage Additive.
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Reproductive height determines the loss of clonal grasses with nitrogen enrichment in a temperate grassland
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作者 Xu Chen Haining Lu +4 位作者 Zhengru Ren Yuqiu Zhang Ruoxuan Liu Yunhai Zhang Xingguo Han 《Plant Diversity》 SCIE CAS CSCD 2024年第2期256-264,共9页
Tall clonal grasses commonly display competitive advantages with nitrogen(N)enrichment.However,it is currently unknown whether the height is derived from the vegetative or reproductive module.Moreover,it is unclear wh... Tall clonal grasses commonly display competitive advantages with nitrogen(N)enrichment.However,it is currently unknown whether the height is derived from the vegetative or reproductive module.Moreover,it is unclear whether the height of the vegetative or reproductive system regulates the probability of extinction and colonization,and determines species diversity.In this study,the impacts on clonal grasses were studied in a field experiment employing two frequencies(twice a year vs.monthly)crossing with nine N addition rates in a temperate grassland,China.We found that the N addition decreased species frequency and increased extinction probability,but did not change the species colonization probability.A low frequency of N addition decreased species frequency and colonization probability,but increased extinction probability.Moreover,we found that species reproductive height was the best index to predict the extinction probability of clonal grasses in N-enriched conditions.The low frequency of N addition may overestimate the negative effect from N deposition on clonal grass diversity,suggesting that a higher frequency of N addition is more suitable in assessing the ecological effects of N deposition.Overall,this study illustrates that reproductive height was associated with the clonal species extinction probability under N-enriched environment. 展开更多
关键词 ANPP Biodiversity Clonal grass COLONIZATION EXTINCTION Nitrogen addition frequency
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Effects of Additives on the Microstructure and Tribology Performance of Ta-12W Alloy Micro-Arc Oxidation Coating
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作者 刘玲 HU Changgang +1 位作者 CHENG Wendong 刘兴泉 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第1期142-149,共8页
Oxide ceramic coatings were fabricated on tantalum alloys by micro-arc oxidation (MAO) to improve their hardness and tribological properties. The MAO coatings were manufactured in a mixed silicatephosphate electrolyte... Oxide ceramic coatings were fabricated on tantalum alloys by micro-arc oxidation (MAO) to improve their hardness and tribological properties. The MAO coatings were manufactured in a mixed silicatephosphate electrolyte containing NaF and/or EDTA (ethylene diamine tetraacetic acid). The surface morphology,cross-sectional view, chemical composition, hardness, and wear performance of the coatings were analysed. As revealed by the scanning electron microscopy, silica-rich nodules appear on the MAO coating obtained in the silicate-phosphate electrolyte, but the formation of nodules is inhibited with NaF and/or EDTA in the electrolyte.Also, they reduce the roughness and improve the compactness of the coatings, which are composed of Ta_(2)O_(5),(Ta, O), and TaO. A thick and hard coating is obtained in the NaF-containing electrolyte, and the tribology performance is effectively improved. With additives, the nodule structure is detached from the coating surface and dissolved in the electrolyte. By using NaF as an electrolyte additive, the abrasion performance of the MAO coating is enhanced by decreasing the nodule structure, increasing the size of micropores, and improving the coating hardness. 展开更多
关键词 micro-arc oxidation tantalum alloy ADDITIVES tribology performance
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Manipulating Crystal Growth and Secondary Phase PbI_(2)to Enable Efficient and Stable Perovskite Solar Cells with Natural Additives
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作者 Yirong Wang Yaohui Cheng +5 位作者 Chunchun Yin Jinming Zhang Jingxuan You Jizheng Wang Jinfeng Wang Jun Zhang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第9期432-448,共17页
In perovskite solar cells(PSCs),the inherent defects of perovskite film and the random distribution of excess lead iodide(PbI_(2))prevent the improvement of efficiency and stability.Herein,natural cellulose is used as... In perovskite solar cells(PSCs),the inherent defects of perovskite film and the random distribution of excess lead iodide(PbI_(2))prevent the improvement of efficiency and stability.Herein,natural cellulose is used as the raw material to design a series of cellulose derivatives for perovskite crystallization engineering.The cationic cellulose derivative C-Im-CN with cyano-imidazolium(Im-CN)cation and chloride anion prominently promotes the crystallization process,grain growth,and directional orientation of perovskite.Meanwhile,excess PbI_(2)is transferred to the surface of perovskite grains or formed plate-like crystallites in local domains.These effects result in suppressing defect formation,decreasing grain boundaries,enhancing carrier extraction,inhibiting non-radiative recombination,and dramatically prolonging carrier lifetimes.Thus,the PSCs exhibit a high power conversion efficiency of 24.71%.Moreover,C-Im-CN has multiple interaction sites and polymer skeleton,so the unencapsulated PSCs maintain above 91.3%of their initial efficiencies after 3000 h of continuous operation in a conventional air atmosphere and have good stability under high humidity conditions.The utilization of biopolymers with excellent structure-designability to manage the perovskite opens a state-of-the-art avenue for manufacturing and improving PSCs. 展开更多
关键词 PEROVSKITE Solar cells Defect passivation Biomass additives Crystal orientation
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A facile strategy for tuning the density of surface-grafted biomolecules for melt extrusion-based additive manufacturing applications
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作者 I.A.O.Beeren G.Dos Santos +8 位作者 P.J.Dijkstra C.Mota J.Bauer H.Ferreira Rui L.Reis N.Neves S.Camarero-Espinosa M.B.Baker L.Moroni 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2024年第3期277-291,共15页
Melt extrusion-based additive manufacturing(ME-AM)is a promising technique to fabricate porous scaffolds for tissue engi-neering applications.However,most synthetic semicrystalline polymers do not possess the intrinsi... Melt extrusion-based additive manufacturing(ME-AM)is a promising technique to fabricate porous scaffolds for tissue engi-neering applications.However,most synthetic semicrystalline polymers do not possess the intrinsic biological activity required to control cell fate.Grafting of biomolecules on polymeric surfaces of AM scaffolds enhances the bioactivity of a construct;however,there are limited strategies available to control the surface density.Here,we report a strategy to tune the surface density of bioactive groups by blending a low molecular weight poly(ε-caprolactone)5k(PCL5k)containing orthogonally reactive azide groups with an unfunctionalized high molecular weight PCL75k at different ratios.Stable porous three-dimensional(3D)scaf-folds were then fabricated using a high weight percentage(75 wt.%)of the low molecular weight PCL 5k.As a proof-of-concept test,we prepared films of three different mass ratios of low and high molecular weight polymers with a thermopress and reacted with an alkynated fluorescent model compound on the surface,yielding a density of 201-561 pmol/cm^(2).Subsequently,a bone morphogenetic protein 2(BMP-2)-derived peptide was grafted onto the films comprising different blend compositions,and the effect of peptide surface density on the osteogenic differentiation of human mesenchymal stromal cells(hMSCs)was assessed.After two weeks of culturing in a basic medium,cells expressed higher levels of BMP receptor II(BMPRII)on films with the conjugated peptide.In addition,we found that alkaline phosphatase activity was only significantly enhanced on films contain-ing the highest peptide density(i.e.,561 pmol/cm^(2)),indicating the importance of the surface density.Taken together,these results emphasize that the density of surface peptides on cell differentiation must be considered at the cell-material interface.Moreover,we have presented a viable strategy for ME-AM community that desires to tune the bulk and surface functionality via blending of(modified)polymers.Furthermore,the use of alkyne-azide“click”chemistry enables spatial control over bioconjugation of many tissue-specific moieties,making this approach a versatile strategy for tissue engineering applications. 展开更多
关键词 Additive manufacturing BLENDING Surface functionalization Surface density Click chemistry HUMAN
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Modeling the effect of stand and site characteristics on the probability of mistletoe infestation in Scots pine stands using remote sensing data
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作者 Luiza Tymińska-Czabańska Piotr Janiec +5 位作者 Pawel Hawrylo Jacek Slopek Anna Zielonka Pawel Netzel Daniel Janczyk Jaroslaw Socha 《Forest Ecosystems》 SCIE CSCD 2024年第3期296-306,共11页
Over the past decade,the presence of mistletoe(Viscum album ssp.austriacum)in Scots pine stands has increased in many European countries.Understanding the factors that influence the occurrence of mistletoe in stands i... Over the past decade,the presence of mistletoe(Viscum album ssp.austriacum)in Scots pine stands has increased in many European countries.Understanding the factors that influence the occurrence of mistletoe in stands is key to making appropriate forest management decisions to limit damage and prevent the spread of mistletoe in the future.Therefore,the main objective of this study was to determine the probability of mistletoe occurrence in Scots pine stands in relation to stand-related endogenous factors such as age,top height,and stand density,as well as topographic and edaphic factors.We used unmanned aerial vehicle(UAV)imagery from 2,247 stands to detect mistletoe in Scots pine stands,while majority stand and site characteristics were calculated from airborne laser scanning(ALS)data.Information on stand age and site type from the State Forest database were also used.We found that mistletoe infestation in Scots pine stands is influenced by stand and site characteristics.We documented that the densest,tallest,and oldest stands were more susceptible to mistletoe infestation.Site type and specific microsite conditions associated with topography were also important factors driving mistletoe occurrence.In addition,climatic water balance was a significant factor in increasing the probability of mistletoe occurrence,which is important in the context of predicted temperature increases associated with climate change.Our results are important for better understanding patterns of mistletoe infestation and ecosystem functioning under climate change.In an era of climate change and technological development,the use of remote sensing methods to determine the risk of mistletoe infestation can be a very useful tool for managing forest ecosystems to maintain forest sustainability and prevent forest disturbance. 展开更多
关键词 Generalized additive models Tree infestation Mistletoe occurrence ALS UAV Scots pine
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From furnace up to freezer:Elevational patterns of plant diversity in Mount Palvar,a semi-arid Irano-Turanian mountain range of southwest Asia
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作者 Atefeh GHORBANALIZADEH Moslem DOOSTMOHAMMADI 《Journal of Mountain Science》 SCIE CSCD 2024年第7期2236-2248,共13页
Much of the world's biodiversity lies in heterogeneous mountain areas with their diverse environments.As an example,Iranian montane ranges are highly diverse,particularly in the Irano-Turanian phytogeographical re... Much of the world's biodiversity lies in heterogeneous mountain areas with their diverse environments.As an example,Iranian montane ranges are highly diverse,particularly in the Irano-Turanian phytogeographical region.Understanding plant diversity patterns with increasing elevation is of high significance,not least for conservation planning.We studied the pattern of species richness,Shannon diversity,endemic richness,endemics ratio,and richness of life forms along a 3900 m elevational transect in Mount Palvar,overlooking the Lut Desert in Southeast Iran.We also analyzed the effect of environmental variables on species turnover along the vertical gradient.A total of 120 vegetation plots(10 m×10 m)were sampled along the elevational transect containing species and environmental data.To discover plant diversity pattern along the elevational gradient,generalized additive model(GAM)was used.Non-metric multidimensional scaling(NMDS)was applied for illustrating the correlation between species composition and environmental variables.We found hump-shaped pattern for species richness,Shannon diversity,endemic richness,and species richness of different life forms,but a monotonic increasing pattern for ratio of endemic species from low to high elevations.Our study confirms the humped pattern of species richness peaking at intermediate elevations along a complete elevational gradient in a semi-arid mountain.The monotonic increase of endemics ratio with elevation in our area as a case study is consistent with global increase of endemism with elevation.According to our results,temperature and precipitation are two important climatic variables that drive elevational plant diversity,particularly in seasonally dry areas.Our study suggests that effective conservation and management are needed for this low latitude mountain area along with calling for long-term monitoring for species redistribution. 展开更多
关键词 Elevational gradient BIODIVERSITY ENDEMIC Generalized additive model Hump-shaped pattern Irano-Turanian region
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Polarizable Additive with Intermediate Chelation Strength for Stable Aqueous Zinc‑Ion Batteries
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作者 Yuting Xia Rongao Tong +5 位作者 Jingxi Zhang Mingjie Xu Gang Shao Hailong Wang Yanhao Dong Chang‑An Wang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第5期41-55,共15页
Aqueous zinc-ion batteries are promising due to inherent safety,low cost,low toxicity,and high volumetric capacity.However,issues of dendrites and side reactions between zinc metal anode and the electrolyte need to be... Aqueous zinc-ion batteries are promising due to inherent safety,low cost,low toxicity,and high volumetric capacity.However,issues of dendrites and side reactions between zinc metal anode and the electrolyte need to be solved for extended storage and cycle life.Here,we proposed that an electrolyte additive with an intermediate chelation strength of zinc ion—strong enough to exclude water molecules from the zinc metal-electrolyte interface and not too strong to cause a significant energy barrier for zinc ion dissociation—can benefit the electrochemical stability by suppressing hydrogen evolution reaction,overpotential growth,and den-drite formation.Penta-sodium diethylene-triaminepentaacetic acid salt was selected for such a purpose.It has a suitable chelating ability in aqueous solutions to adjust solvation sheath and can be readily polarized under electrical loading conditions to further improve the passivation.Zn||Zn symmetric cells can be stably operated over 3500 h at 1 mA cm^(-2).Zn||NH4V4O10 full cells with the additive show great cycling stability with 84.6%capacity retention after 500 cycles at 1 A g^(-1).Since the additive not only reduces H2 evolution and corrosion but also modifies Zn2+diffusion and deposition,highlyreversible Zn electrodes can be achieved as verified by the experimental results.Our work offers a practical approach to the logical design of reliable electrolytes for high-performance aqueous batteries. 展开更多
关键词 Aqueous zinc-ion batteries Electrolyte additives DTPA-Na Chelation strength
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