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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 of pore structural parameters of granular activated carbons derived from different coals and their blends 被引量:7
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作者 Yao Xin Xie Qiang +3 位作者 Yang Chuan Zhang Bo Wan Chaoran Cui Shanshan 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2016年第4期661-667,共7页
A series of granular activated carbons (GACs) were prepared by briquetting method from Chinese coals of different ranks and their blends, with coal pitch as the binder. Pore structural parameters including BET speci... A series of granular activated carbons (GACs) were prepared by briquetting method from Chinese coals of different ranks and their blends, with coal pitch as the binder. Pore structural parameters including BET specific surface area (SBEr), total pore volume (Vr) and average pore diameter (da) were measured and cal- culated as well as process parameters such as yield of char (CY) and burn-off (B). The relationship between the pore structural parameters of the GAC from coal blend (BC-GAC) and the ones of the GACs from corresponding single coals (SC-GACs) was analyzed, in which an index, the relative error (δ), was presented to define the bias between fitted values and experimental values of these parameters of the BC-GACs. The results show that the BC-GAC keeps qualitatively the pore structural features of the SC-GACs; as concerned as the quantitative relationship, the pore structural parameters of the BC-GAC from coal blend consisting of non-caking coals can be obtained by adding proportionally the pore structural parameters of the SC-GACs with a less than 10%. Meanwhile, for the BC-GAC from coal blend containing weak caking bituminous coal, the δ increases up to 25% and the experimental pore size distribution differs greatly from the fitted one. 展开更多
关键词 Granular activated carbon Coal blend Pore structural parameters additivity
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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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基于ASP-SERes2Net的说话人识别算法
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作者 令晓明 陈鸿雁 +1 位作者 张小玉 张真 《北京工业大学学报》 CAS 北大核心 2025年第1期42-50,共9页
为提升说话人识别的特征提取能力,解决在噪声环境下识别率低的问题,提出一种基于残差网络的说话人识别算法——ASP-SERes2Net。首先,采用梅尔语谱图作为神经网络的输入;其次,改进Res2Net网络的残差块,并且在每个残差块后引入压缩激活(sq... 为提升说话人识别的特征提取能力,解决在噪声环境下识别率低的问题,提出一种基于残差网络的说话人识别算法——ASP-SERes2Net。首先,采用梅尔语谱图作为神经网络的输入;其次,改进Res2Net网络的残差块,并且在每个残差块后引入压缩激活(squeeze-and-excitation,SE)注意力模块;然后,用注意力统计池化(attention statistics pooling,ASP)代替原来的平均池化;最后,采用附加角裕度的Softmax(additive angular margin Softmax,AAM-Softmax)对说话人身份进行分类。通过实验,将ASP-SERes2Net算法与时延神经网络(time delay neural network,TDNN)、ResNet34和Res2Net进行对比,ASP-SERes2Net算法的最小检测代价函数(minimum detection cost function,MinDCF)值为0.0401,等误率(equal error rate,EER)为0.52%,明显优于其他3个模型。结果表明,ASP-SERes2Net算法性能更优,适合应用于噪声环境下的说话人识别。 展开更多
关键词 说话人识别 梅尔语谱图 Res2Net 压缩激活(squeeze-and-excitation SE)注意力模块 注意力统计池化(attention statistics pooling ASP) 附加角裕度的Softmax(additive angular margin Softmax AAM-Softmax)
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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 62G10 62G20 62G07
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Anti-amyloid antibodies in Alzheimer’s disease: what did clinical trials teach us?
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作者 Danko Jeremic Lydia Jiménez-Díaz Juan D.Navarro-López 《Neural Regeneration Research》 SCIE CAS 2025年第4期1092-1093,共2页
Although many causes of Alzheimer’s disease(AD)may exist,both the original amyloid cascade and tau hypotheses posit that abnormal misfolding and accumulation of amyloid-β(Aβ)and tau protein is the central event cau... Although many causes of Alzheimer’s disease(AD)may exist,both the original amyloid cascade and tau hypotheses posit that abnormal misfolding and accumulation of amyloid-β(Aβ)and tau protein is the central event causing the pathology.However,that conclusion could be only partly true,and there is conflicting evidence about the role of both proteins in AD,being able to precede and influence one another.Some researchers argue that these proteins are mere executors rather than primary causes of pathology.Therefore,there have been continuing refinements of both hypotheses,with alternative explanations proposed.Aβand tau proteins may be independently involved in specific neurotoxic pathways;yet there may be other crucial processes going on in early AD.Moreover,accumulating evidence suggests that Aβand tau act synergistically,rather than additively in disease onset(Jeremic et al.,2021,2023a). 展开更多
关键词 AMYLOID ALZHEIMER additive
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Efficient and Stable Perovskite Solar Cells and Modules Enabled by Tailoring Additive Distribution According to the Film Growth Dynamics
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作者 Mengen Ma Cuiling Zhang +5 位作者 Yujiao Ma Weile Li Yao Wang Shaohang Wu Chong Liu Yaohua Mai 《Nano-Micro Letters》 SCIE EI CAS 2025年第2期387-400,共14页
Gas quenching and vacuum quenching process are widely applied to accelerate solvent volatilization to induce nucleation of perovskites in blade-coating method.In this work,we found these two pre-crystallization proces... Gas quenching and vacuum quenching process are widely applied to accelerate solvent volatilization to induce nucleation of perovskites in blade-coating method.In this work,we found these two pre-crystallization processes lead to different order of crystallization dynamics within the perovskite thin film,resulting in the differences of additive distribution.We then tailor-designed an additive molecule named 1,3-bis(4-methoxyphenyl)thiourea to obtain films with fewer defects and holes at the buried interface,and prepared perovskite solar cells with a certified efficiency of 23.75%.Furthermore,this work also demonstrates an efficiency of 20.18%for the large-area perovskite solar module(PSM)with an aperture area of 60.84 cm^(2).The PSM possesses remarkable continuous operation stability for maximum power point tracking of T_(90)>1000 h in ambient air. 展开更多
关键词 Gas quenching Additive distribution Buried passivation Blade coating Crystallization dynamics
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Robust interface and excellent as-built mechanical properties of Ti–6Al–4V fabricated through laser-aided additive manufacturing with powder and wire
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作者 Fei Weng Guijun Bi +5 位作者 Youxiang Chew Shang Sui Chaolin Tan Zhenglin Du Jinlong Su Fern Lan Ng 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第1期154-168,共15页
The feasibility of manufacturing Ti-6Al-4V samples through a combination of laser-aided additive manufacturing with powder(LAAM_(p))and wire(LAAM_(w))was explored.A process study was first conducted to successfully ci... The feasibility of manufacturing Ti-6Al-4V samples through a combination of laser-aided additive manufacturing with powder(LAAM_(p))and wire(LAAM_(w))was explored.A process study was first conducted to successfully circumvent defects in Ti-6Al-4V deposits for LAAM_(p) and LAAM_(w),respectively.With the optimized process parameters,robust interfaces were achieved between powder/wire deposits and the forged substrate,as well as between powder and wire deposits.Microstructure characterization results revealed the epitaxial prior β grains in the deposited Ti-6Al-4V,wherein the powder deposit was dominated by a finerα′microstructure and the wire deposit was characterized by lamellar α phases.The mechanisms of microstructure formation and correlation with mechanical behavior were analyzed and discussed.The mechanical properties of the interfacial samples can meet the requirements of the relevant Aerospace Material Specifications(AMS 6932)even without post heat treatment.No fracture occurred within the interfacial area,further suggesting the robust interface.The findings of this study highlighted the feasibility of combining LAAM_(p) and LAAM_(w) in the direct manufacturing of Ti-6Al-4V parts in accordance with the required dimensional resolution and deposition rate,together with sound strength and ductility balance in the as-built condition. 展开更多
关键词 laser-aided additive manufacturing powder deposition wire deposition interfacial characteristic mechanical behavior
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Satellite remote sensing reveals overwhelming recovery of forest from disturbances in Asia
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作者 Yiying Zhu Hesong Wang Anzhi Zhang 《Atmospheric and Oceanic Science Letters》 2025年第1期46-51,共6页
Forest ecosystems play key roles in mitigating human-induced climate change through enhanced carbon uptake;however,frequently occurring climate extremes and human activities have considerably threatened the stability ... Forest ecosystems play key roles in mitigating human-induced climate change through enhanced carbon uptake;however,frequently occurring climate extremes and human activities have considerably threatened the stability of forests.At the same time,detailed accounts of disturbances and forest responses are not yet well quantified in Asia.This study employed the Breaks For Additive Seasonal and Trend method-an abrupt-change detection method-to analyze the Enhanced Vegetation Index time series in East Asia,South Asia,and Southeast Asia.This approach allowed us to detect forest disturbance and quantify the resilience after disturbance.Results showed that 20%of forests experienced disturbance with an increasing trend from 2000 to 2022,and Southeast Asian countries were more severely affected by disturbances.Specifically,95%of forests had robust resilience and could recover from disturbance within a few decades.The resilience of forests suffering from greater magnitude of disturbance tended to be stronger than forests with lower disturbance magnitude.In summary,this study investigated the resilience of forests across the low and middle latitudes of Asia over the past two decades.The authors found that most forests exhibited good resilience after disturbance and about two-thirds had recovered to a better state in 2022.The findings of this study underscore the complex relationship between disturbance and resilience,contributing to comprehension of forest resilience through satellite remote sensing. 展开更多
关键词 Forest ecosystem Enhanced vegetation index Breaks for additive seasonal and trend method DISTURBANCE RESILIENCE
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;oxicity models of metal mixtures established on the basis o "additivity" and "interactions"
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作者 Yang Liu Martina G. Vijver +1 位作者 Bo Pan Willie J. G. M. Peijnenburg 《Frontiers of Environmental Science & Engineering》 SCIE EI CAS CSCD 2017年第2期11-23,共13页
Observed effects of metal mixtures on animals and plants often differ from the estimates, which are commonly calculated by adding up the biological responses of individual metals. This difference from additivity is co... Observed effects of metal mixtures on animals and plants often differ from the estimates, which are commonly calculated by adding up the biological responses of individual metals. This difference from additivity is commonly referred to as being a consequence of specific interactions between metals. The science of how to quantify metal interactions and whether to include them in risk assessment models is in its infancy. This review summarizes the existing predictive tools for evaluating the combined toxicity of metals present in mixtures and indicates the advantages and disadvantages of each method. We intend to provide eco-toxicologists with background information on how to make good use of the tools and how to advance the methods for assessing toxicity of metal mixtures, It is concluded that statistically significant deviations from additivity are not necessarily biologically relevant. Incorporation of interactions between metals in a model does not on forehand mean that the model is more accurate than a model developed based on additivity only. It is recommended to first use a relatively simple method for effect prediction of uninvestigated metal mixtures. To improve the reliability of toxicity modeling for metal mixtures, further efforts should focus on balancing the relationship between the significance of statistics and the biological meaning, and unraveling the toxicity mechanisms of metals and their mixtures. 展开更多
关键词 METAL MIXTURES TOXICITY additivity Modeling INTERACTIONS
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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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Scale-Invariant Occupancy of Phase Space and Additivity of Nonextensive Entropy S_q
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作者 赵伟 伞冶 《Journal of Shanghai Jiaotong university(Science)》 EI 2010年第4期441-446,共6页
Phase space can be constructed for N equal and distinguishable binary subsystems which are correlated in a scale-invariant manner. In the paper, correlation coefficient and reduced probability are introduced to charac... Phase space can be constructed for N equal and distinguishable binary subsystems which are correlated in a scale-invariant manner. In the paper, correlation coefficient and reduced probability are introduced to characterize the scale-invariant correlated binary subsystems. Probabilistic sets for the correlated binary subsystems satisfy Leibnitz triangle rule in the sense that the marginal probabilities of N-system are equal to the joint probabilities of the (N - 1)-system. For entropic index q ≠ 1, nonextensive entropy Sq is shown to be additive in the scale-invariant occupation of phase space. 展开更多
关键词 nonextensive entropy additivity correlation SCALE-INVARIANCE
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Species-specific and generalized allometric biomass models for eight Fagaceae species in the understory of evergreen broadleaved forests in subtropical China
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作者 Shengwang Meng 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第4期156-170,共15页
Quantifying the biomass of saplings in the regeneration component is critical for understanding biogeochemical processes of forest ecosystems.However,accurate allometric equations have yet to be developed in sufficien... Quantifying the biomass of saplings in the regeneration component is critical for understanding biogeochemical processes of forest ecosystems.However,accurate allometric equations have yet to be developed in sufficient detail.To develop species-specific and generalized allometric equations,154 saplings of eight Fagaceae tree species in subtropical China’s evergreen broadleaved forests were collected.Three dendrometric variables,root collar diameter(d),height(h),and crown area(ca)were applied in the model by the weighted nonlinear seemingly unrelated regression method.Using only d as an input variable,the species-specific and generalized allometric equations estimated the aboveground biomass reasonably,with R _(adj)^(2) values generally>0.85.Adding h and/or ca improved the fitting of some biomass components to a certain extent.Generalized equations showed a relatively large coefficient of variation but comparable bias to species-specific equations.Only in the absence of species-specific equations at a given location are generalized equations for mixed species recommended.The developed regression equations can be used to accurately calculate the aboveground biomass of understory Fagaceae regeneration trees in China’s subtropical evergreen broadleaved forests. 展开更多
关键词 ALLOMETRY Aboveground biomass additivity Regeneration Subtropical China
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Polarizable Additive with Intermediate Chelation Strength for Stable Aqueous Zinc‑Ion Batteries 被引量:2
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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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Synthetic polymers:A review of applications in drilling fluids 被引量:2
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作者 Shadfar Davoodi Mohammed Al-Shargabi +2 位作者 David A.Wood Valeriy S.Rukavishnikov Konstantin M.Minaev 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期475-518,共44页
With the growth of deep drilling and the complexity of the well profile,the requirements for a more complete and efficient exploitation of productive formations increase,which increases the risk of various complicatio... With the growth of deep drilling and the complexity of the well profile,the requirements for a more complete and efficient exploitation of productive formations increase,which increases the risk of various complications.Currently,reagents based on modified natural polymers(which are naturally occurring compounds)and synthetic polymers(SPs)which are polymeric compounds created industrially,are widely used to prevent emerging complications in the drilling process.However,compared to modified natural polymers,SPs form a family of high-molecular-weight compounds that are fully synthesized by undergoing chemical polymerization reactions.SPs provide substantial flexibility in their design.Moreover,their size and chemical composition can be adjusted to provide properties for nearly all the functional objectives of drilling fluids.They can be classified based on chemical ingredients,type of reaction,and their responses to heating.However,some of SPs,due to their structural characteristics,have a high cost,a poor temperature and salt resistance in drilling fluids,and degradation begins when the temperature reaches 130℃.These drawbacks prevent SP use in some medium and deep wells.Thus,this review addresses the historical development,the characteristics,manufacturing methods,classification,and the applications of SPs in drilling fluids.The contributions of SPs as additives to drilling fluids to enhance rheology,filtrate generation,carrying of cuttings,fluid lubricity,and clay/shale stability are explained in detail.The mechanisms,impacts,and advances achieved when SPs are added to drilling fluids are also described.The typical challenges encountered by SPs when deployed in drilling fluids and their advantages and drawbacks are also discussed.Economic issues also impact the applications of SPs in drilling fluids.Consequently,the cost of the most relevant SPs,and the monomers used in their synthesis,are assessed.Environmental impacts of SPs when deployed in drilling fluids,and their manufacturing processes are identified,together with advances in SP-treatment methods aimed at reducing those impacts.Recommendations for required future research addressing SP property and performance gaps are provided. 展开更多
关键词 Synthetic versus natural polymers Nanopolymers Drilling fluid additives LUBRICITY Clay swelling Hole cleaning
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Rationally designing electrolyte additives for highly improving cyclability of LiNi_(0.5)Mn_(1.5)O_(4)/Graphite cells 被引量:2
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作者 Zhiyong Xia Kuan Zhou +8 位作者 Xiaoyan Lin Zhangyating Xie Qiurong Chen Xiaoqing Li Jie Cai Suli Li Hai Wang Mengqing Xu Weishan Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第4期266-275,共10页
High voltage is necessary for high energy lithium-ion batteries but difficult to achieve because of the highly deteriorated cyclability of the batteries.A novel strategy is developed to extend cyclability of a high vo... High voltage is necessary for high energy lithium-ion batteries but difficult to achieve because of the highly deteriorated cyclability of the batteries.A novel strategy is developed to extend cyclability of a high voltage lithium-ion battery,LiNi_(0.5)Mn_(1.5)O_(4)/Graphite(LNMO/Graphite)cell,which emphasizes a rational design of an electrolyte additive that can effectively construct protective interphases on anode and cathode and highly eliminate the effect of hydrogen fluoride(HF).5-Trifluoromethylpyridine-trime thyl lithium borate(LTFMP-TMB),is synthesized,featuring with multi-functionalities.Its anion TFMPTMB-tends to be enriched on cathode and can be preferentially oxidized yielding TMB and radical TFMP-.Both TMB and radical TFMP can combine HF and thus eliminate the detrimental effect of HF on cathode,while the TMB dragged on cathode thus takes a preferential oxidation and constructs a protective cathode interphase.On the other hand,LTFMP-TMB is preferentially reduced on anode and constructs a protective anode interphase.Consequently,a small amount of LTFMP-TMB(0.2%)in 1.0 M LiPF6in EC/DEC/EMC(3/2/5,wt%)results in a highly improved cyclability of LNMO/Graphite cell,with the capacity retention enhanced from 52%to 80%after 150 cycles at 0.5 C between 3.5 and 4.8 V.The as-developed strategy provides a model of designing electrolyte additives for improving cyclability of high voltage batteries. 展开更多
关键词 Electrolyte additive Design and synthesis CYCLABILITY High voltage batteries Cathode and anode interphases
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ZnO Additive Boosts Charging Speed and Cycling Stability of Electrolytic Zn–Mn Batteries 被引量:2
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作者 Jin Wu Yang Tang +6 位作者 Haohang Xu Guandie Ma Jinhong Jiang Changpeng Xian Maowen Xu Shu‑Juan Bao Hao Chen 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第4期293-304,共12页
Electrolytic aqueous zinc-manganese(Zn–Mn) batteries have the advantage of high discharge voltage and high capacity due to two-electron reactions. However, the pitfall of electrolytic Zn–Mn batteries is the sluggish... Electrolytic aqueous zinc-manganese(Zn–Mn) batteries have the advantage of high discharge voltage and high capacity due to two-electron reactions. However, the pitfall of electrolytic Zn–Mn batteries is the sluggish deposition reaction kinetics of manganese oxide during the charge process and short cycle life. We show that, incorporating ZnO electrolyte additive can form a neutral and highly viscous gel-like electrolyte and render a new form of electrolytic Zn–Mn batteries with significantly improved charging capabilities. Specifically, the ZnO gel-like electrolyte activates the zinc sulfate hydroxide hydrate assisted Mn^(2+) deposition reaction and induces phase and structure change of the deposited manganese oxide(Zn_(2)Mn_(3)O_8·H_(2)O nanorods array), resulting in a significant enhancement of the charge capability and discharge efficiency. The charge capacity increases to 2.5 mAh cm^(-2) after 1 h constant-voltage charging at 2.0 V vs. Zn/Zn^(2+), and the capacity can retain for up to 2000 cycles with negligible attenuation. This research lays the foundation for the advancement of electrolytic Zn–Mn batteries with enhanced charging capability. 展开更多
关键词 Electrolytic aqueous zinc-manganese batteries Electrolyte pH value ZnO electrolyte additive Fast constant-voltage charging ability
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Review on laser directed energy deposited aluminum alloys 被引量:2
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作者 Tian-Shu Liu Peng Chen +7 位作者 Feng Qiu Hong-Yu Yang Nicholas Tan Yew Jin Youxiang Chew Di Wang Ruidi Li Qi-Chuan Jiang Chaolin Tan 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第2期84-131,共48页
Lightweight aluminum(Al)alloys have been widely used in frontier fields like aerospace and automotive industries,which attracts great interest in additive manufacturing(AM)to process high-value Al parts.As a mainstrea... Lightweight aluminum(Al)alloys have been widely used in frontier fields like aerospace and automotive industries,which attracts great interest in additive manufacturing(AM)to process high-value Al parts.As a mainstream AM technique,laser-directed energy deposition(LDED)shows good scalability to meet the requirements for large-format component manufacturing and repair.However,LDED Al alloys are highly challenging due to their inherent poor printability(e.g.low laser absorption,high oxidation sensitivity and cracking tendency).To further promote the development of LDED high-performance Al alloys,this review offers a deep understanding of the challenges and strategies to improve printability in LDED Al alloys.The porosity,cracking,distortion,inclusions,element evaporation and resultant inferior mechanical properties(worse than laser powder bed fusion)are the key challenges in LDED Al alloys.Processing parameter optimizations,in-situ alloy design,reinforcing particle addition and field assistance are the efficient approaches to improving the printability and performance of LDED Al alloys.The underlying correlations between processes,alloy innovation,characteristic microstructures,and achievable performances in LDED Al alloys are discussed.The benchmark mechanical properties and primary strengthening mechanism of LDED Al alloys are summarized.This review aims to provide a critical and in-depth evaluation of current progress in LDED Al alloys.Future opportunities and perspectives in LDED high-performance Al alloys are also outlined. 展开更多
关键词 additive manufacturing laser directed energy deposition(LDED) aluminum alloys PRINTABILITY aluminum matrix composite auxiliary fields mechanical properties
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The biological functions and metabolic pathways of valine in swine 被引量:1
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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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