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Human milk phospholipid substitutes improve miceÊs cognitive behavior and brain lipid profile
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作者 Teng Wei Yanping Wu +4 位作者 Jiaxin Shen Manman Zhang Yong Sun Zeyuan Deng Jing Li 《Food Science and Human Wellness》 2026年第2期623-634,共12页
Although human milk fat substitute(HMFS)has been wildly applied in infant formula(IF),there are still some differences in fat composition between human milk and IF,which is extremely attributed to the phospholipid com... Although human milk fat substitute(HMFS)has been wildly applied in infant formula(IF),there are still some differences in fat composition between human milk and IF,which is extremely attributed to the phospholipid composition.We therefore designed a human milk phospholipid substitute(HMPS),and investigated its nutritional outcomes on brain development using C57BL/6J mice.Results showed that HMPS improved mice's cognitive behavior and dendritic development compared to soybean phospholipids and nophospholipid diets.Based on the lipidomics,we revealed that these beneficial outcomes were potentially associated with the increased biosynthesis of N-acylethanolamines,phosphatidylethanolamine(PE),and ether PE,and the decreased metabolism of diacylglycerol and hexosylceramide in brain.It was further found in Kyoto Encyclopedia of Genes and Genomes analysis that glycerophospholipid metabolic pathway participated in the improvement of HMPS on mice's neurodevelopment.In conclusion,this study demonstrated that HMPS improves mice's neurodevelopment,and the glycerophospholipid metabolic pathway plays a major role in this beneficial result,and provided evidence for future application of HMPS in commercial IF. 展开更多
关键词 Human milk phospholipid substitute NEURODEVELOPMENT Brain lipidomics Phosphatidylethanolamine(PE) Ether PE
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Effects of molecular conformation on buried interface passivation and efficient perovskite solar cell realization employing fluorine substituted benzoic acid
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作者 Boyan Li Rongbo Wang +8 位作者 Ya Wang Wentao Wu Weitao Yan Handong Zhang Xingyuan Zhong Juntao Zhao Liyi Yao Wei-Hua Wang Yi Ding 《Journal of Energy Chemistry》 2026年第1期826-831,I0018,共7页
Benzoic acid containing fluorine atom at ortho-,meta-,and para-position are employed as self-assembled monolayers to modify the buried interface in perovskite solar cells(PSCs).It is demonstrated that the position of ... Benzoic acid containing fluorine atom at ortho-,meta-,and para-position are employed as self-assembled monolayers to modify the buried interface in perovskite solar cells(PSCs).It is demonstrated that the position of fluorine atom influences the passivation effect and para-fluorinated one provided the most substantial performance enhancement mainly originating from ameliorated contact and energy band alignment between NiOx and perovskite,improved perovskite quality and defect healing.Resultantly,PSC with a power conversion efficiency of 24%can be achieved.Meanwhile,which can maintain 96.8%of the initial PCE after a 1000 h storage,presenting enhanced durability.This work highlights the critical role of molecular functionality and conformation in the buried interface modification of PSCs,providing valuable insights for future developments. 展开更多
关键词 Perovskite solar cells F atom substituted benzoic acids Buried interface modification
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Space cannot substitute for time in the study of the ecosystem services-human wellbeing relationship 被引量:1
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作者 Lumeng Liu Jianguo Wu 《Geography and Sustainability》 2025年第2期57-68,共12页
The relationship between ecosystem services(ES)and human well-being(HWB)is fundamental to the science and practice of sustainability.However,studies have shown conflicting results,which has been attributed to the infl... The relationship between ecosystem services(ES)and human well-being(HWB)is fundamental to the science and practice of sustainability.However,studies have shown conflicting results,which has been attributed to the influences of indicators,contexts,and scales.Yet,another potential factor,which has been overlooked,may be the mixed use of spatial and temporal approaches.Using twelve ES and seven well-being indicators and multiple statistical methods,we quantified and compared the spatial and temporal ES–HWB relationships for Inner Mongolia,China.The spatial and temporal relationships differed in both correlation direction and strength.Most relationships of economic and employment-related indicators with food provisioning and supporting services were temporally positive but spatially nonsignificant or negative.Some relationships of economic and employmentrelated indicators with water retention,sandstorm prevention,and wind erosion were temporally negative but spatially complex.However,the spatial and temporal ES–HWB relationships could also be similar in some cases.We conclude that although both the spatial and temporal approaches have merits,space generally cannot substitute for time in the study of ES–HWB relationship.Our study helps reconcile the seemingly conflicting findings in the literature,and suggests that future studies should explicitly distinguish between the spatial and temporal ES–HWB relationships. 展开更多
关键词 Ecosystem services Objective human well-being Space-for-time substitution Spatial relationship Temporal relationship
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Stabilizing the solid-solution sodium storage in Cr-substituted Na_(3)V_(2)(PO_(4))_(3) cathode for aqueous sodium-ion batteries with long-term stability 被引量:1
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作者 Qinyan Jian Tinghong Gao +4 位作者 Wensheng Yang Xinhai Wang Lishan He Jiarui Liu Yunjun Ruan 《Journal of Energy Chemistry》 2025年第6期797-805,I0016,共10页
Aqueous sodium-ion batteries(ASIBs) offer significant advantages for energy storage on a large scale,attributed to their economical cost,secure operatio n,and eco-friend ly natu re.Among the leading cathode materials ... Aqueous sodium-ion batteries(ASIBs) offer significant advantages for energy storage on a large scale,attributed to their economical cost,secure operatio n,and eco-friend ly natu re.Among the leading cathode materials for ASIBs,Na_(3)V_(2)(PO_(4))_(3)(NVP) exhibits excellent structural stability and a high Na+diffusion coefficient,making it a promising option.However,the high solubility of vanadium-based materials in aqueous electrolytes engenders suboptimal cycling stability for Na_(3)V_(2)(PO_(4))_(3),constraining its application in ASIBs.Herein,the Cr-substituted Na_(3)V_(1.3)Cr_(0.7)(PO_(4))3@C(NV_(1.3)Cr_(0.7)P) cathode material was synthesized via a simple sol-gel method.It is found that Cr substitution reduces the cell parameters of NV_(1.3)Cr_(0.7)P,effectively reinforcing the crystal structure.Furthermore,NV_(1.3)Cr_(0.7)P alters the Na^(+)insertion/extraction mechanism,transforming the typical two-phase reaction between Na_(1)V_(2)(PO_(4))_(3)and Na_(3)V_(2)(PO_(4))3into continuous solid-solution reactions with stable intermediates.The Cr substitution diminishes the sodium-ion diffusion energy barrier in NV_(1.3)Cr_(0.7)P,leading to smoother Na+insertion and extraction processes.Consequently,NV_(1.3)Cr_(0.7)P exhibits impressive cycling stability,retaining 74.8% of its capacity after 5,000 cycles at a current density of 5 A g^(-1),along with an outstanding rate performance of 79,2% at 10 A g^(-1).This work elucidates the stable Na^(+)insertion/extraction processes in Cr-substituted NV_(1.3)Cr_(0.7)P,offering insights into the application of vanadium-based materials in aqueous sodium-ion batteries. 展开更多
关键词 Na_(3)V_(2)(PO_(4))_(3) Cr substitution Insertion/extraction mechanism Long-term cycling stability Aqueous sodium-ion battery
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Bioengineered skin-substitutes incorporating rete-ridges using a bioprinting process
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作者 SooJung Chae SeoYul Jo +7 位作者 Dogeon Yoon Ji-Seon Lee WonJin Kim JaeYoon Lee Ji-Hye Park You-rin Kim Wook Chun GeunHyung Kim 《International Journal of Extreme Manufacturing》 2025年第1期522-541,共20页
Bioprinting is a widely used technique for creating three-dimensional,complex,and heterogeneous artificial tissue constructs that are biologically and biophysically similar to natural tissues.The skin is composed of s... Bioprinting is a widely used technique for creating three-dimensional,complex,and heterogeneous artificial tissue constructs that are biologically and biophysically similar to natural tissues.The skin is composed of several layers including the epidermis,basement membrane(BM),and dermis.However,the unique undulating structure of basement membranes(i.e.rete ridges)and the function of BM have not been extensively studied in the fabrication of engineered skin substitutes.In this study,a novel engineered skin substitute incorporating an artificially designed rete ridge(i.e.mogul-shape)was developed using bioprinting and bioinks prepared using collagen and fibrinogen.To mimic the structure of the rete ridges of skin tissue,we developed a modified bioprinting technique,controlling rheological property of bioink to create a mogul-shaped layer.In vitro cellular activities,including the expression of specific genes(those encoding vimentin,laminin-5,collagen IV,and cytokeratins),demonstrated that the engineered skin substitute exhibited more potent cellular responses than the normally bioprinted control owing to the favorable biophysical BM structure and the bioink microenvironment.Additionally,the feasibility of utilizing the bioprinted skin-structure was evaluated in a mouse model,and in vivo results demonstrated that the bioprinted skin substitutes effectively promoted wound healing capabilities.Based on these results,we suggest that bioprinted skin tissues and the bioprinting technique for mimicking rete ridges can be used not only as potential lab-chip models for testing cosmetic materials and drugs,but also as complex physiological models for understanding human skin. 展开更多
关键词 collagen FIBRINOGEN basement membrane skin substitute BIOPRINTING
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Effect of magnesium slag and blast furnace slag as partial cement substitutes on properties of cemented tailings backfill
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作者 YANG Jian YANG Xiao-bing +3 位作者 YAN Ze-peng YIN Sheng-hua ZHANG Xi-zhi QI Yao-bin 《Journal of Central South University》 2025年第7期2696-2716,共21页
Utilizing mine solid waste as a partial cement substitute(CS)to develop new cementitious materials is a significant technological innovation that will decrease the expenses associated with filling mining.To realize th... Utilizing mine solid waste as a partial cement substitute(CS)to develop new cementitious materials is a significant technological innovation that will decrease the expenses associated with filling mining.To realize the resource utilization of magnesium slag(MS)and blast furnace slag(BFS),the effects of different contents of MS and BFS as partial CSs on the deformation and energy characteristics of cemented tailings backfill on different curing ages(3,7,and 28 d)were discussed.Meanwhile,the destabilization failure energy criterion of the backfill was established from the direction of energy change.The results show that the strength of all backfills increased with increasing curing age,and the strengths of the backfills exceeded 1.342 MPa on day 28.The backfill with 50%BFS+50%cement has the best performance in mechanical properties(the maximum strength can reach 6.129 MPa)and is the best choice among these CS combinations.The trend in peak strain and elastic modulus of the backfill with increasing curing age may vary depending on the CS combination.The energy index at peak stress of the backfill with BFS as a partial CS was significantly higher than that of the backfill under other CS combinations.In contrast,the enhancement of the energy index when MS was used as a partial CS was not as significant as BFS.Sharp changes in the energy consumption ratio after continuous smooth changes can be used as a criterion for destabilization and failure of the backfill.The research results can provide guidance for the application of MS and BFS as partial CSs in mine filling. 展开更多
关键词 cemented tailings backfill cement substitute curing age mechanical properties energy evolution energy consumption ratio
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Outcomes of autologous bone grafts vs bone substitutes in tibial plateau fractures:A meta-analysis
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作者 Ali Saad Alshahrani Yazan Jumah Alalwani +8 位作者 Nihal Mushabb Alqahtani Abdullah Shafi D Alanazi Ahmed Khaled Almarri Shatha Saud Alqurashi Deemah Khalid Ghazi Abdullah Musaaed Alsalamah Rahaf Hamdan Alruwaili Ahmed Y Azzam Fawaz Alanii 《World Journal of Orthopedics》 2025年第9期56-66,共11页
BACKGROUND Tibial plateau fractures often require structural support for metaphyseal defects created during articular reduction.While autologous bone grafting has been utilized as the gold standard,bone substitutes of... BACKGROUND Tibial plateau fractures often require structural support for metaphyseal defects created during articular reduction.While autologous bone grafting has been utilized as the gold standard,bone substitutes offer advantages including reduced donor site morbidity.Our meta-analysis evaluated the comparative efficacy of these approaches across clinical and operative outcomes.AIM To conduct a systematic review and meta-analysis of randomized controlled trials comparing autologous bone grafts with bone substitutes for tibial plateau fractures.METHODS We conducted a systematic review and meta-analysis of randomized controlled trials comparing autologous bone grafts with bone substitutes for tibial plateau fractures.Primary outcomes included joint depression,secondary collapse rate,operative time,blood loss,and infection rate.Subgroup analyses were performed by fracture complexity,geographic region,and methodological factors.In addition to that,we also developed a combined outcome score integrating structural,procedural,and complication domains.RESULTS Seven randomized controlled trials with 424 patients(296 bone substitute,128 autograft)were included.No significant differences in joint depression or secondary collapse were observed across fracture complexity categories.Geographic variations were evident,with Western studies showing significantly higher risk of secondary collapse with autografts(risk ratio=1.45,P value=0.02).Both Western and Asian studies have demonstrated significantly reduced blood loss with bone substitutes(70-90 mL less),while operative time reduction was more significant in the Asian studies(23.65 vs 8.00 minutes,P value=0.04 for subgroup difference).The combined outcome score(standardized effect size-0.2481)favored bone substitutes,primarily due to procedural advantages.CONCLUSION Bone substitutes provide similar structural outcomes to autologous bone grafts while having better procedural advantages in tibial plateau fracture management.These findings support bone substitutes as a viable option across fracture patterns.Future studies should focus on specific bone substitute formulations and cost-effectiveness analyses. 展开更多
关键词 Tibial plateau fractures TIBIA Bone grafts Bone substitutes Synthetic bone material
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Copper-substituted P3-type Na_(0.54)Mn_(0.64)Fe_(_(0.1)6)Mg_(0.1)Cu_(0.1)O_(2) cathode material for sodium-ion batteries with enhanced anionic redox reversibility
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作者 Zhe Mei Xun-Lu Li +10 位作者 Cui Ma Jie Zeng Chong-Yu Du Rui-Jie Luo Xuan Xu Zhe Qian Zi-Ting Zhou Ya Zhang Qian Cheng Yao-Guo Fang Yong-Ning Zhou 《Rare Metals》 2025年第5期2986-2996,共11页
P3-type manganese-iron-based cathodes with high specific capacity and abundant resource have attracted considerable attention for sodium-ion batteries.However,the long-term cycle stability of P3-type cathodes is still... P3-type manganese-iron-based cathodes with high specific capacity and abundant resource have attracted considerable attention for sodium-ion batteries.However,the long-term cycle stability of P3-type cathodes is still not satisfactory.In this work,we design a new quaternary manganese-iron-based cathode material(P3-Na_(0.54)Mn_(0.64)Fe_(_(0.1)6)Mg_(0.1)Cu_(0.1)O_(2))by Cu substitution.The strong covalent Cu-O bonds improve the structural stability and the reversibility of O redox during charge and discharge processes.Cu substitution also mitigates the structure change with less unit cell volume variation,and improves the Na-ion transport kinetics effectively.As a result,NMFMC delivers much improved cycling stability and rate capability compared with NMFM.It reveals that the charge compensation of NMFMC is mainly contributed by Mn^(3+/4+),Fe^(3+/3.5+)and O_(2-/-)during the charge and discharge processes,and Cu substitution can also enhance the activity and reversibility of Fe redox.This strategy provides a new pathway toward improving the stability and O redox reversibility of P3-type cathode materials for sodium-ion batteries. 展开更多
关键词 Sodium-ion batteries Cathode materials Cu substitution Anionic redox reversibility
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Review of the structural properties and interfacial reactions of Al-substituted goethite,hematite and ferrihydrite
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作者 Yu LIANG Hongfeng CHEN +2 位作者 Jinling XU Mingxia WANG Wenfeng TAN 《Pedosphere》 2025年第1期42-52,共11页
Isomorphic substitution of ferric ion(Fe~(3+))by aluminum ion(Al~(3+))in iron(hydro)oxides is ubiquitous in natural environments.Aluminum substitution inevitably leads to changes in the microstructures,physicochemical... Isomorphic substitution of ferric ion(Fe~(3+))by aluminum ion(Al~(3+))in iron(hydro)oxides is ubiquitous in natural environments.Aluminum substitution inevitably leads to changes in the microstructures,physicochemical properties,and surface reactions of iron(hydro)oxides,which may have great impacts on the sequestration of nutrients and contaminants in soils and aquatic environments.Over the past decades,the structural properties and surface reactivity of Al-substituted iron(hydro)oxides have been intensively studied.Iron(hydro)oxides in various structural forms and with different Al substitution amounts present high application potentials in addressing environmental issues.A timely summary of the structural properties and interfacial reactions of the most common and representative Al-substituted iron(hydro)oxides is of significance.Herein,the effects of Al substitution on the structural properties and surface activities of iron(hydro)oxides were clarified according to the microstructure,crystal facets,surface site type and density,interfacial reaction mechanisms,and modeling parameters of iron(hydro)oxides.This review systematically elucidates how Al substitution affects the structural properties and surface reactions of iron(hydro)oxides,including the well crystallized goethite and hematite and the poorly crystallized ferrihydrite,providing theoretical guidance for further exploration of the mineralogical characteristics and environmental geochemical behaviors of iron(hydro)oxides. 展开更多
关键词 adsorption defective structure iron(hydro)oxide isomorphic substitution surface active site surface charge behavior
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Advances in the In Situ Synthesis of Hydrogen Peroxide Using Hydrogen Substitutes
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作者 Xiao Cai Weiping Ding Yan Zhu 《Carbon and Hydrogen》 2025年第1期10-19,共10页
Hydrogen peroxide(H_(2)O_(2)),as a prevalently green oxidant in the chemical industry,confronts many bottlenecks in the conventional anthraquinone-based methods,such as organic solvents dependency,energy-intensive com... Hydrogen peroxide(H_(2)O_(2)),as a prevalently green oxidant in the chemical industry,confronts many bottlenecks in the conventional anthraquinone-based methods,such as organic solvents dependency,energy-intensive complex operations and inherent safety risks from centralized production.The direct synthesis route from H_(2) coupled with O_(2) presents a promising alternative,but remains constrained by the safety requirement and the reaction control demand.This article systematically reviews breakthroughs in non-hydrogen catalytic systems for in situ synthesis of H_(2)O_(2).Through elucidating the mechanism of two-electron oxygen reduction pathways,renewable hydrogen substitutes with enhanced safety including CO,HCOOH,glucose and alcohols have been highlighted.Their efficient conversion of O_(2) to H_(2)O_(2) and the integration with sustainable processes such as selective oxidation are also discussed.It is expected to provide fundamental insights into the synergistic mechanism in heterogeneous catalysis and offer a new viewpoint for developing a decentralized H_(2)O_(2) synthesis system for practical applications,moving toward a greener and more economical H_(2)O_(2) production approach. 展开更多
关键词 heterogeneous catalysis hydrogen peroxide hydrogen substitutes
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数字经济对新型产业工人就业的影响机理与效应研究 被引量:1
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作者 杜家廷 何瑾 +1 位作者 张泽义 顾谦农 《西北人口》 北大核心 2026年第2期85-100,共16页
作为经济发展新引擎,数字经济正深刻改变着新型产业工人的就业结构与方式。数字经济的发展不仅能够通过数字基础设施拓宽新型产业工人职业发展路径和就业渠道,同时还能够降低就业信息搜寻成本,减少摩擦性失业,是缓解我国企业“招工难”... 作为经济发展新引擎,数字经济正深刻改变着新型产业工人的就业结构与方式。数字经济的发展不仅能够通过数字基础设施拓宽新型产业工人职业发展路径和就业渠道,同时还能够降低就业信息搜寻成本,减少摩擦性失业,是缓解我国企业“招工难”与新型产业工人“就业难”并存困局的重要途径。文章基于2011~2022年我国30个省份(不包括西藏和港澳台)的面板数据样本,运用动态门槛效应模型、工具变量两阶段最小二乘法(Ⅳ-2SLS)和空间面板杜宾模型研究数字经济对新型产业工人就业的影响。结果表明:(1)数字经济发展对新型产业工人就业具有显著促进作用。由于边际效应递减规律的存在,这种促进作用具有门槛非线性特征。(2)数字经济对新型产业工人就业的影响存在异质性。相比新生代新型产业工人低占比区、受教育低水平区和程序性工种高聚集区,数字经济在新生代新型产业工人高占比区、受教育高水平区和程序性工种低聚集区对新型产业工人就业的促进作用更显著。(3)数字经济主要通过生产效率提升机制、新兴业态催生机制和虚拟集聚发展机制为新型产业工人提供更多岗位,从而促进新型产业工人就业水平提升。同时,数字经济对新型产业工人就业的影响存在空间效应,邻近地区数字经济发展对本地数字资源要素产生虹吸作用。基于此,建议大力夯实数字基础设施,不断提升数字经济与新型产业工人就业政策的针对性和协同性,积极畅通数字经济促进新型产业工人就业的路径机制。 展开更多
关键词 数字经济 替代效应 信息不对称 门槛效应模型
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新质生产力背景下竹资源多途径综合利用全产业链的构建
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作者 孙云娟 罗彦卿 +3 位作者 丁玉 杜官本 王戈 蒋剑春 《林产化学与工业》 北大核心 2026年第1期1-14,共14页
围绕新质生产力背景下竹资源多途径综合利用全产业链的构建,介绍了“以竹代塑”的国内外发展形势,包括提出以“以竹代塑”的时代背景、“以竹代塑”的发展机遇,以及竹资源的优势。阐述了“以竹代塑”的全产业链的发展现状,涵盖竹类资源... 围绕新质生产力背景下竹资源多途径综合利用全产业链的构建,介绍了“以竹代塑”的国内外发展形势,包括提出以“以竹代塑”的时代背景、“以竹代塑”的发展机遇,以及竹资源的优势。阐述了“以竹代塑”的全产业链的发展现状,涵盖竹类资源现状、创新技术产品研发、机械装备发展和高质量发展政策等方面。总结了“以竹代塑”全产业链在竹林培育、竹材加工产业链效能、竹产业创新人才和政策支持力度等方面的发展困境。最后提出了夯实竹资源培育建设、加强竹材采运和加工创新升级、强化科技与人才支撑、加强政策支持力度、深化国际合作与交流等建设性意见。 展开更多
关键词 种质资源 复合材料 以竹代塑
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植物蛋白基乳液凝胶脂肪替代物研究进展
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作者 朱秀清 王子涵 +4 位作者 黄雨洋 郭汝杞 刘琳琳 王颖 朱颖 《食品科学》 北大核心 2026年第4期305-314,共10页
随着消费者健康饮食意识的增强,脂肪替代物的开发日益受到关注。植物蛋白因其良好的功能特性,常被用作乳化剂或凝胶剂,在脂肪替代方面展现出巨大潜力,已成为研究热点。植物蛋白基乳液凝胶不仅具有营养价值,且在形态与口感上也与动物脂... 随着消费者健康饮食意识的增强,脂肪替代物的开发日益受到关注。植物蛋白因其良好的功能特性,常被用作乳化剂或凝胶剂,在脂肪替代方面展现出巨大潜力,已成为研究热点。植物蛋白基乳液凝胶不仅具有营养价值,且在形态与口感上也与动物脂肪相似;但在实际应用中,仍存在质地偏软、稳定性不足等问题。本文系统综述了植物蛋白基乳液凝胶的制备方法,重点探讨了不同添加物及制备方法对植物蛋白基乳液凝胶脂肪替代物结构和特性的影响及其机制,并总结和展望了其作为脂肪替代物在食品中的应用及未来研究方向,以期为植物基脂肪替代物的研究开发与应用提供理论依据。 展开更多
关键词 植物蛋白 乳液凝胶 脂肪替代物 制备方法 结构 特性
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西北干旱区梨园有机肥替代与行间生草的土壤改良效应研究
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作者 尹志荣 解艳玲 +2 位作者 王昊 陈永伟 马文礼 《中国土壤与肥料》 北大核心 2026年第2期19-30,共12页
为探索西北干旱区高pH、低肥力梨园土壤的可持续改良途径,评估有机肥替代、不同草种行间种植及水肥管理对土壤关键性质(理化性状、微生物、酶活性)的影响,并识别主要驱动因子。在宁夏高pH(>8.4)梨园进行两年田间试验,结合L16正交设计... 为探索西北干旱区高pH、低肥力梨园土壤的可持续改良途径,评估有机肥替代、不同草种行间种植及水肥管理对土壤关键性质(理化性状、微生物、酶活性)的影响,并识别主要驱动因子。在宁夏高pH(>8.4)梨园进行两年田间试验,结合L16正交设计与4种草种比较,系统测定了土壤理化性质、微生物丰度及关键酶活性。结果表明,与原始土壤相比,行间生草处理普遍提升了土壤有机质(如黑麦草处理达16.70 g·kg^(-1))、速效养分(如百脉根处理速效钾达277.40 mg·kg^(-1))、微生物丰度(如黑麦草处理细菌丰度达8.7×106 cfu·g^(-1))及蔗糖酶(如百脉根处理达4.56 mg·g^(-1)·min^(-1))、脲酶活性(如黑麦草处理达3.29 mg·g^(-1)·min^(-1)),显示出基础培肥效果。然而,在高pH土壤背景下,生草未能显著改变pH。方差分析进一步明确,有机肥替代比例[显著影响有效磷(P<0.01),速效钾(P<0.01)]和草种选择[显著影响有机质(P<0.05)、有效磷(P<0.05),且极显著影响放线菌丰度(P<0.001)]是调控多数土壤养分和微生物指标的关键驱动因子。基于主成分分析,在16种管理组合中,黑麦草+高灌水量+常规施肥+低锌肥与百脉根+低灌水量+5%有机肥替代+低锌肥是协同改善土壤微生物丰度与综合肥力的最优组合。不同草种功能分化显著,在改善特定土壤属性方面各具优势。土壤酶活性与养分状况高度正相关(如脲酶、碱性磷酸酶与有机质/碱解氮相关系数>0.9,P<0.001),而微生物总丰度与多数功能指标关联较弱。主成分分析亦揭示pH与综合肥力/酶活性存在主导性的负相关梯度。在该高pH干旱梨园生态系统中,优化有机肥替代比例和选择功能互补的行间草种是促进土壤健康的核心策略。行间生草效果受高pH环境显著制约。在此类土壤条件下,酶活性比微生物总丰度更能敏感地反映土壤功能状态。 展开更多
关键词 行间生草 土壤酶活性 土壤微生物 土壤养分 有机肥替代
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开放式创新、独占机制与创新绩效:竞合关系的调节机制与“替代—互补”效应
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作者 蔡双立 陈晨 马洪梅 《现代财经(天津财经大学学报)》 北大核心 2026年第1期37-55,共19页
随着数字技术快速发展与产业融合的加速,企业间网络关系日益复杂,如何平衡企业间竞争与合作、“共享”与“保护”的张力,提高企业创新绩效已成为学界和业界的核心议题。本研究基于1995—2021年的发明专利申请数据,系统检验了开放式创新... 随着数字技术快速发展与产业融合的加速,企业间网络关系日益复杂,如何平衡企业间竞争与合作、“共享”与“保护”的张力,提高企业创新绩效已成为学界和业界的核心议题。本研究基于1995—2021年的发明专利申请数据,系统检验了开放式创新与独占机制对探索式创新绩效和利用式创新绩效的非线性影响及竞合关系的调节效应。研究发现:开放式创新对探索式创新绩效和利用式创新绩效均表现出倒U型影响,独占机制对二者呈U型影响,且影响曲线均存在异质性;合作关系强化了开放式创新和独占机制对利用式创新绩效的影响,但削弱了开放式创新对探索式创新绩效的影响;相比之下,竞争关系弱化了二者对利用式创新绩效的影响,强化了独占机制对探索式创新绩效的影响,同时也扭曲了合作关系对开放式创新(独占机制)与利用式创新绩效关系的调节作用。进一步分析表明,在利用式创新绩效的导向下,竞合关系在不同开放—独占区间呈现替代与互补的双模态效应,而在探索式创新绩效的导向下,竞争与合作则始终表现为互补机制。本研究结论揭示了开放式创新与独占机制嵌入外部竞合环境的复杂作用机理,拓展了开放式创新与知识产权保护的研究边界,并为企业在动态竞合环境下优化创新战略、提升双元创新绩效提供了理论支持。 展开更多
关键词 开放式创新 独占机制 知识产权保护 竞合关系 互补与替代效应
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黑水虻虫粪施用对番茄产量品质及土壤理化性质的影响
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作者 王莉 祁杰 +4 位作者 杜静 孔祥平 王聪 朱飞 叶小梅 《中国土壤与肥料》 北大核心 2026年第2期125-131,共7页
为了比较黑水虻虫粪与传统有机肥在番茄上的施用效果,并明确黑水虻虫粪氮替代化肥氮在番茄上施用的最优比例,本研究开展了黑水虻虫粪及腐熟鸡粪不同比例有机肥氮替代化肥氮施用对番茄产量品质及土壤理化性质的影响。大田试验的结果显示,... 为了比较黑水虻虫粪与传统有机肥在番茄上的施用效果,并明确黑水虻虫粪氮替代化肥氮在番茄上施用的最优比例,本研究开展了黑水虻虫粪及腐熟鸡粪不同比例有机肥氮替代化肥氮施用对番茄产量品质及土壤理化性质的影响。大田试验的结果显示,20%~40%虫粪氮替代化肥氮能达到同等比例腐熟鸡粪氮替代化肥氮的产量,维持番茄的稳产增产,但50%虫粪氮替代化肥氮处理组相较于其他处理组减产了6.6%~10.7%。虫粪和腐熟鸡粪不同比例的施用均不同程度提高了番茄可溶性固形物、维生素C和硝酸盐含量,其中可溶性固形物含量提升幅度为5.5%~10%,维生素C含量在30%腐熟鸡粪和40%腐熟鸡粪氮替代化肥氮处理组出现了显著提升,硝酸盐含量在40%虫粪和50%腐熟鸡粪氮替代化肥氮处理组出现了显著提升。腐熟鸡粪和虫粪的施用使土壤电导率、有机质、全氮、碱解氮、有效磷和速效钾含量均出现了一定幅度的升高,提升幅度分别为10.7%~50.0%、4.5%~19.8%、33.8%~70.7%、21.2%~62.0%、52.0%~98.1%、11.9%~40.5%。综上,20%~30%虫粪氮替代化肥氮能达到同等比例腐熟鸡粪氮替代化肥氮的产量,维持番茄的稳产增产,且能提高番茄品质和土壤质量。 展开更多
关键词 虫粪 有机肥氮替代化肥氮 番茄 产量 品质 土壤理化性质
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学术期刊“影子审稿”中团队成员替审行为规范及改进措施
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作者 张洁 马欣荣 杨峰 《编辑学报》 北大核心 2026年第1期58-63,共6页
同行评审在学术期刊论文发表过程中起着关键作用。同行评审中的团队成员替审作为“影子审稿”的一种,尽管被定义为学术不端行为,但因其行为的隐蔽性和普遍性禁而不止。同行评审中团队成员替审行为一直行走在审稿的灰色地带,一定程度上... 同行评审在学术期刊论文发表过程中起着关键作用。同行评审中的团队成员替审作为“影子审稿”的一种,尽管被定义为学术不端行为,但因其行为的隐蔽性和普遍性禁而不止。同行评审中团队成员替审行为一直行走在审稿的灰色地带,一定程度上支撑着期刊的正常运行,这启发我们规范和改进这一审稿行为。本文通过对替审、团队审稿和协作审稿的多维度比较,同时借鉴国际同行实践,认为赋予团队替审者合法的身份,变团队成员替审为团队成员共同审稿可有效解决这一问题。在加强对共同审稿人培训和保密意识教育的基础上,通过监督问责机制杜绝评审过程的学术不端行为,通过评价激励机制让优秀的团队成员成为独立审稿人。借助良好的“编辑—作者”互动,为团队共同审稿人搭建成长的平台,使他们完成从“作者—审稿人”到“核心作者—优秀审稿人”的转变,实现其职业生涯成长和期刊高质量发展的双赢。 展开更多
关键词 团队成员替审行为 团队成员共同审稿 学术期刊 “影子审稿” 学术不端 同行评审
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合同无效与履约保证金返还——探索超越“全有或全无”的第三条道路
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作者 韩世远 《云南社会科学》 北大核心 2026年第1期107-117,共11页
因合同无效,基于该合同给付的履约保证金依法可以主张返还,相应的返还请求权通常是给付不当得利返还请求权。履约保证金作为给付不当得利请求返还,通常作为“返还财产”即为已足,无须“折价补偿”(价额偿还)。“得利”可以表现为对金钱... 因合同无效,基于该合同给付的履约保证金依法可以主张返还,相应的返还请求权通常是给付不当得利返还请求权。履约保证金作为给付不当得利请求返还,通常作为“返还财产”即为已足,无须“折价补偿”(价额偿还)。“得利”可以表现为对金钱的受领,“返还财产”则须依不当得利法则确定其返还的方法与范围,可能但却并非必然是当初所受领的金钱。在接力给付形成给付链条且两份合同均属无效(双重瑕疵)场合,善意的接力给付人的现存利益可能表现为其对第三人的不当得利请求权,该请求权作为接力给付人所受领履约保证金的代偿物,构成相应的返还客体。这种“双重不当得利请求权”能够精准对应当事人事先对于履约保证金返还风险的分配,因其给予每个人其所应得,故更为公正。 展开更多
关键词 不当得利 履约保证金 返还财产 代偿物 给付链条
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创造性破坏:新质生产力重塑就业结构的效应洞察
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作者 戴翔 林欣雨 《南方经济》 北大核心 2026年第1期26-52,共27页
基于阿吉翁“创造性破坏”非均衡失业理论框架,文章探讨了数字技术驱动的新一轮工业革命下,新质生产力发展对企业就业的双重影响。理论分析指出,新质生产力通过提升全要素生产率和优化资源配置下的要素替代,对就业同时产生替代与创造效... 基于阿吉翁“创造性破坏”非均衡失业理论框架,文章探讨了数字技术驱动的新一轮工业革命下,新质生产力发展对企业就业的双重影响。理论分析指出,新质生产力通过提升全要素生产率和优化资源配置下的要素替代,对就业同时产生替代与创造效应,且该过程受企业规模的调节影响。通过创新性测度企业层面新质生产力发展水平并基于2012—2022年中国上市公司微观数据,证实了上述理论预判和机制的存在。现阶段,替代效应的“破坏性”超越创造效应,对就业总量形成抑制作用;但创造效应显著推动了人力资本积累等劳动力要素升级,表明发展新质生产力有助于促进高质量充分就业。企业内部收入差距与人机协同效应的证据提供了进一步佐证。异质性分析表明,非国有企业、非高科技行业、要素市场发达地区及东部地区企业,新质生产力对低技能劳动力的替代效应和对中高技能劳动力的创造效应均更显著。该研究为理解新质生产力重塑就业结构提供了微观证据,并为有效应对其可能引发的不利冲击和挑战、促进高质量就业开拓了新思路。 展开更多
关键词 新质生产力 就业结构 替代效应 创造效应
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Antoioxidant Activity of Carboxymethyl Chitosan with Different Substituted Degrees 被引量:15
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作者 姚倩 孙涛 +1 位作者 周冬香 毛芳 《Agricultural Science & Technology》 CAS 2008年第1期5-7,59,共4页
[Objective] In order to study the relations among different positions, degrees of substitution and antioxidant ability. [Method] N, O-carboxymethyl chitosan (NOA, NOB and NOC)with various degrees of substitution (D... [Objective] In order to study the relations among different positions, degrees of substitution and antioxidant ability. [Method] N, O-carboxymethyl chitosan (NOA, NOB and NOC)with various degrees of substitution (DS)were obtained by etherizing chito-oligosacchaside. Their structure and substituted degree were characterized and their antioxldant activity to·OH was evaluated. [ Result] The IC50 s of NOA ,NOB and NOC were 0.15 ,0. 29 ,0. 23 mg/ml while their DSs of -NH2 position(DSN) were 0.51,0.29 and 0.38 and DSo were 0. 74 ,0. 84 ,0. 97respectively.[ Conclusion] With the increase of DSN ,antioxidant activity of N,O-carboxymethyl chitosan oligosaccharide to·OH was up. 展开更多
关键词 Chitosan oligosaccharide Carboxymethyl chitosan oligosaccharide Degree of substitution Antioxidant activity
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