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Redox status regulates eggshell color by modulating protoporphyrin IX biosynthesis via the SIRT1/PGC-1α/ALAS1 axis in brown-shelled hens
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作者 Yu Fu Mingyuan Lu +4 位作者 Dongkai Liu Jianping Wang haijun zhang Guanghai Qi Jing Wang 《Journal of Animal Science and Biotechnology》 2026年第1期426-442,共17页
Background This study investigated the molecular mechanisms by which redox status regulates protoporphyrin IX(PpIX)biosynthesis and eggshell coloration in brown-shelled laying hens.This study consisted of two experime... Background This study investigated the molecular mechanisms by which redox status regulates protoporphyrin IX(PpIX)biosynthesis and eggshell coloration in brown-shelled laying hens.This study consisted of two experiments involving 48 and 32 healthy 60-week-old Hy-Line Brown hens,respectively.The hens exhibited either dark(L*=51.99±2.08)or light(L*=64.12±3.02)brown eggshell colors.In Exp.1,light brown-shelled hens were fed a basal diet(Lb group),while dark brown-shelled hens received either a basal diet(Db group)or a basal diet with 10 mg/kg ammonium metavanadate(Dbv group)for 20 d.In Exp.2,light brown-shelled hens received either a basal diet(Lbc group)or a basal diet supplemented with 200 mg/kg resveratrol(Lbr group)for 12 weeks.Results Compared to the Db group,eggshell L*values increased,and PpIX concentrations in both eggshell and uterus decreased in Dbv and Lb groups.These groups also showed oxidative stress,as indicated by reduced hepatic T-SOD and CAT activities.Uterine redox status changes were further confirmed by increased T-AOC level(Dbv)and reduced CAT gene expression(Lb).These redox disturbances led to reduced expression of ND4 and COX1 mt DNA,decreased ATP production and CS activity,along with upregulation of IR,PI3K,HK,and PK gene expression,reflecting altered mitochondrial energy metabolism.Notably,the SIRT1/PGC-1αsignaling cascade and its downstream target ALAS1 were significantly downregulated at both mRNA and protein levels in Dbv and Lb groups.Compared to the Lbc group,the Lbr group exhibited higher antioxidant capacity by increasing hepatic CAT activity and uterine T-SOD and GSH-Px activities,and reducing MDA levels.Moreover,the Lbr group restored mitochondrial function and PpIX biosynthesis by upregulating ND4 and COX1 mt DNA,CS and SDHA gene expression,and SIRT1/PGC-1α/ALAS1 signaling,while downregulating LDH activity and the expression of IR and PI3K,thereby alleviating eggshell color fading.Conclusion Oxidative stress induces eggshell depigmentation by impairing mitochondrial function and downregulating the SIRT1/PGC-1α/ALAS1 pathway,leading to reduced PpIX biosynthesis.Specifically,vanadium-induced or endogenous oxidative stress disrupts mitochondrial energy metabolism and suppresses key components of this pathway,while resveratrol alleviates oxidative damage and restores mitochondrial function and ALAS1-driven PpIX synthesis through reactivation of the SIRT1/PGC-1αaxis. 展开更多
关键词 Eggshell depigmentation MITOCHONDRION Oxidative stress Protoporphyrin IX SIRT1/PGC-1α
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Object-oriented Software Construction Based on the Integration of OBE and BOPPPS Models
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作者 Jianghong Ma Cuiyun Gao +5 位作者 Min Fang Jianlong Wu Miao zhang Zhiting Zhao haijun zhang Yunming Ye 《计算机教育》 2026年第3期148-157,共10页
This study presents a teaching reform for the Object-oriented Software Construction(OOSC)course by integrating outcome-based education(OBE)and the BOPPPS(bridge-In,objectives,pre-assessment,participatory learning,post... This study presents a teaching reform for the Object-oriented Software Construction(OOSC)course by integrating outcome-based education(OBE)and the BOPPPS(bridge-In,objectives,pre-assessment,participatory learning,post-assessment,summary)instructional model.The reform addresses the gap between syntax-based programming instruction and the need for higher-level skills in abstraction,modularity,and software architecture.The course is anchored in a semester-long,project-based learning platform centered on a Java-based Aircraft Battle Game,progressing through six iterative experiments.Each experiment targets specific competencies within the structured BOPPPS teaching cycle and is aligned with specific OBE learning outcomes.A case study on the Factory Pattern illustrates how the BOPPPS model fosters conceptual understanding and practical application.Evaluation results from the 2023 and 2024 spring semesters show improved outcomes:Project completion rose from 87%to 95%,37%of students implemented innovative features,and average final grades increased by 7%.The results affirm that the OBE+BOPPPS integration strengthens engagement,deepens understanding,and equips students with real-world software development competencies. 展开更多
关键词 OOSC JAVA Design pattern OBE+BOPPPS
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激光增材制造Inconel 718基复合材料及力学性能
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作者 钟巧芳 李梦洁 +3 位作者 胡燕秋 屈超 张海军 刘江昊 《化学进展》 北大核心 2025年第9期1384-1396,共13页
Inconel 718(IN718)合金具有优异的高温强度、高延展性和良好的耐蚀性,在航空航天、军工及能源等领域有广阔应用前景。然而,IN718合金较低的硬度和耐磨性严重限制了其应用领域拓展。针对此问题,可行的解决策略之一是对IN718合金进行表... Inconel 718(IN718)合金具有优异的高温强度、高延展性和良好的耐蚀性,在航空航天、军工及能源等领域有广阔应用前景。然而,IN718合金较低的硬度和耐磨性严重限制了其应用领域拓展。针对此问题,可行的解决策略之一是对IN718合金进行表面或基体的组成/结构改性。激光增材制造方法可有效地调控复合材料的组成和显微结构,从而优化其综合力学性能。本文首先介绍了IN718基复合材料的性质特点和改性思路,随后明确了IN718基复合材料激光增材制造方法的优越性和局限性,并且概括了激光增材制造IN718基复合材料的显微结构及力学性能的演变规律,最后总结了IN718基复合材料的组成设计、制备方法改进、显微结构调控和力学性能优化等方面的关键科学问题,进而对本领域研究的未来发展方向作出了展望。 展开更多
关键词 IN718基复合材料 激光增材制造 表面改性 基体改性 显微结构 力学性能
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Comparative effects of selenium-enriched lactobacilli and selenium-enriched yeast on performance,egg selenium enrichment,antioxidant capacity,and ileal microbiota in laying hens 被引量:1
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作者 Jianmin Zhou Uchechukwu Edna Obianwuna +6 位作者 Longfei zhang Yongli Liu haijun zhang Kai Qiu Jing Wang Guanghai Qi Shugeng Wu 《Journal of Animal Science and Biotechnology》 2025年第3期1399-1415,共17页
Background Organic selenium(Se)has gained recognition in poultry nutrition as a feed additive to boost production and Se deposition in eggs and tissues,owing to its high bioavailability,efficient tissue accumulation a... Background Organic selenium(Se)has gained recognition in poultry nutrition as a feed additive to boost production and Se deposition in eggs and tissues,owing to its high bioavailability,efficient tissue accumulation and minimal toxicity.Selenium-enriched yeast(SeY)is a well-established source,while selenium-enriched lactobacilli(SeL),a newer alternative,offers the added benefits of probiotics.This study examined the effects of SeY and SeL on egg quality,antioxidant capacity,Se deposition,and gut health in laying hens.After a two-week pre-treatment with a Sedeficient diet(SeD),450 Hy-Line Brown laying hens(30-week-old)were assigned into five dietary groups with six replicates of 15 hens each.The groups included a SeD,SeD supplemented with 1.5 mg Se/kg from SeY(SeY15),or 1.5,3.0,and 6.0 mg Se/kg from SeL(SeL15,SeL30,SeL60).The feeding trial lasted for 12 weeks.Results SeY15 and SeL15 improved the feed-to-egg ratio(P<0.05)in the latter stages.Haugh units were significantly increased(P<0.05)in the SeY15 and SeL30 groups,while darker yolk color(P<0.05)was observed in the SeY15,SeL15,and SeL60 groups.All Se-supplemented diets increased Se content in whole eggs,albumen,and yolk(P<0.05),while SeL groups showed a dose-dependent effect.Antioxidant enzyme activities increased,and MDA content decreased in the serum(P<0.05),with SeY15 showing the highest GSH-Px levels(P<0.05).SeL60 increased serum alkaline phosphatase and aspartate transaminase,and distorted the liver architecture(P<0.05).Se-diets reduced concentrations of reactive oxygen species(ROS)in the ileum and liver(P<0.05).SeL15 improved the ileal villus height-tocrypt depth ratio(P<0.05).SeY15 and/or SeL15 up-regulated TXNRD1 and SEPHS1 mRNA while down-regulating SCLY expression in the liver.SeY15 altered ileal microbiota by increasing both beneficial and pathogenic bacteria,whereas SeL15 predominantly boosted beneficial bacteria.Conclusion SeL integrates the antioxidant properties of organic Se with the probiotic benefits on gut health,resulting in a performance-enhancing effect comparable to that of SeY.However,high SeL level(6.0 mg Se/kg)compromised productivity and metabolic functions while enhancing Se deposition. 展开更多
关键词 Antioxidant capacity Egg selenium Feed efficiency Gut microbiota Laying hen Selenium-enriched lactobacilli Selenium-enriched yeast
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Zhongfeng Xingnao Liquid ameliorates post-stroke cognitive impairment through sirtuin1(SIRT1)/nuclear factor erythroid 2-related factor 2(Nrf2)/heme oxygenase 1(HO-1)pathway 被引量:1
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作者 Wenqin Yang Wen Wen +4 位作者 Hao Chen haijun zhang Yun Lu Ping Wang Shijun Xu 《Chinese Journal of Natural Medicines》 2025年第1期77-89,共13页
The activation of the sirtuin1(SIRT1)/nuclear factor erythroid 2-related factor 2(Nrf2)/heme oxygenase 1(HO-1)pathway has been shown to mitigate oxidative stress-induced apoptosis and mitochondrial damage by reducing ... The activation of the sirtuin1(SIRT1)/nuclear factor erythroid 2-related factor 2(Nrf2)/heme oxygenase 1(HO-1)pathway has been shown to mitigate oxidative stress-induced apoptosis and mitochondrial damage by reducing reactive oxygen species(ROS)levels.Clinical trials have demonstrated that Zhongfeng Xingnao Liquid(ZFXN)ameliorates post-stroke cognitive impairment(PSCI).However,the underlying mechanism,particularly whether it involves protecting mitochondria and inhibiting apoptosis through the SIRT1/Nrf2/HO-1 pathway,remains unclear.This study employed an oxygen-glucose deprivation(OGD)cell model using SHSY5Y cells and induced PSCI in rats through modified bilateral carotid artery ligation(2VO).The effects of ZFXN on learning and memory,neuroprotective activity,mitochondrial function,oxidative stress,and the SIRT1/Nrf2/HO-1 pathway were evaluated both in vivo and in vitro.Results indicated that ZFXN significantly increased the B-cell lymphoma 2(Bcl2)/Bcl2-associated X(Bax)ratio,reduced terminal deoxynucleotidyl transferase-mediated d UTP nickend-labeling(TUNEL)+cells,and markedly improved cognition,synaptic plasticity,and neuronal function in the hippocampus and cortex.Furthermore,ZFXN exhibited potent antioxidant activity,evidenced by decreased ROS and malondialdehyde(MDA)content and increased superoxide dismutase(SOD),catalase(CAT),and glutathione(GSH)levels.ZFXN also demonstrated considerable enhancement of mitochondrial membrane potential(MMP),Tom 20 fluorescence intensity,adenosine triphosphate(ATP)and energy charge(EC)levels,and mitochondrial complexⅠandⅢactivity,thereby inhibiting mitochondrial damage.Additionally,ZFXN significantly increased SIRT1 activity and elevated SIRT1,nuclear Nrf2,and HO-1 levels.Notably,these effects were substantially counteracted when SIRT1 was suppressed by the inhibitor EX-527 in vitro.In conclusion,ZFXN alleviates PSCI by activating the SIRT1/Nrf2/HO-1 pathway and preventing mitochondrial damage. 展开更多
关键词 Zhongfeng Xingnao Liquid Post-stroke cognitive impairment Oxidative stress Mitochondrial function Apoptosis Sirtuin1/nuclear factor erythroid 2-related factor 2/heme oxygenase 1 pathway
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Identification and molecular marker development for peel color gene in melon(Cucumis melo L.) 被引量:1
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作者 Jian Ma Guoliang Yuan +4 位作者 Xinyang Xu haijun zhang Yanhong Qiu Congcong Li Huijun zhang 《Journal of Integrative Agriculture》 2025年第7期2589-2600,共12页
Peel color is an important appearance quality of melons that significantly affects consumer preferences.In this study,a near-isogenic line NIL-G(dark green peel)was generated from B8(grey-green peel)and B15(white peel... Peel color is an important appearance quality of melons that significantly affects consumer preferences.In this study,a near-isogenic line NIL-G(dark green peel)was generated from B8(grey-green peel)and B15(white peel).The F_2 population constructed by crossing NIL-G and B15 was used to study the inheritance pattern of peel color,and bulked-segregant analysis sequencing(BSA-seq)was employed to identify the interval in which the target gene was located.Genetic analysis showed that a dominant gene controls the dark green peel trait at maturity.BSAseq and molecular markers were used to localize the candidate gene in a 263.7 kb interval of chromosome 4,which contained the CmAPRR2 gene with known functions.Moreover,allelic sequence analysis revealed four SNP variations of the CmAPRR2 gene in B15,of which SNP.G614331A was located at the junction of the 6th exon and 6th intron.The G-to-A mutation caused alternative splicing of the transcript of CmAPRR2 in B15,generating two transcripts(CmAPRR2-A and CmAPRR2-B)with premature termination codons.Furthermore,the Kompetitive Allele Specific PCR(KASP)marker,APRR2-G/A,was developed based on this SNP and shown to co-segregate with the peel color phenotype in the F_(2) population.Compared to white-peel B15,the expression level of CmAPRR2 in dark green peel NIL-G was higher at each growth stage.Therefore,CmAPRR2 may be the key gene controlling the fruit color of melons.This study identified a novel allelic variant of CmAPRR2 that leads to white peel formation in mature melons.We also provides a theoretical basis for further research on the gene regulatory mechanism of melon peel colors,which promotes using molecular marker-assisted selection to modify melon peel colors in the future. 展开更多
关键词 MELON BSA-seq MAPPING CmAPRR2 peel color KASP marker
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Supplementation of serine in low-gossypol cottonseed meal-based diet improved egg white gelling and rheological properties by regulating ovomucin synthesis and magnum physiological function in laying hens 被引量:1
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作者 Jianmin Zhou Yu Fu +5 位作者 Uchechukwu Edna Obianwuna Jing Wang haijun zhang Xiubo Li Guanghai Qi Shugeng Wu 《Journal of Integrative Agriculture》 2025年第3期1152-1166,共15页
This study examined the effect of dietary serine(Ser)on egg white quality,ovomucin content of laying hens fed low-gossypol cottonseed meal(LCSM)-based diet and sought to explore the regulatory mechanism underlying the... This study examined the effect of dietary serine(Ser)on egg white quality,ovomucin content of laying hens fed low-gossypol cottonseed meal(LCSM)-based diet and sought to explore the regulatory mechanism underlying the effects.A total of 288 Hy-Line Brown layers were randomly assigned into 3 treatments and respectively offered soybean meal(SBM)-based diet,LCSM-based diet,and LCSM-based diet supplemented with 0.435%L-Ser.Dietary Ser supplementation reversed the decrease in quality indices of albumen,including the proportion of thick albumen(P<0.05),thick-to-thin ratio(P<0.05),albumen height(P<0.05),Haugh unit(P<0.05),and apparent viscosity that were caused by LCSM intake.Also,dietary Ser supplementation mitigated the LCSM-induced reduction in ovomucin content of the albumen(P<0.05).FT-IR analysis of ovomucin revealed differences in second derivative spectra at 1,200-800 cm^(-1) between birds received SBM-and LCSM-based diets,meanwhile,the α-helix of ovomucin was decreased by LCSM but increased by Ser addition(P<0.05).Furthermore,Ser addition up-regulated the mRNA expression of β-ovomucin in magnum mucosa at 2 and 7.5 h post-oviposition(P<0.05).Ser mitigated the LCSMinduced impairment of magnum epithelium,increased goblet cell counts(P<0.05),and up-regulated the expression of occludin,mucin 2,and the relevant glycosyltransferases for O-glycosylation in magnum mucosa(P<0.05).Conclusively,the alleviating effect of Ser on declining albumen quality due to dietary LCSM,could be explained by the efficacy of Ser in regulating ovomucin synthesis.This regulation occurred at the levels of transcription and posttranscriptional O-glycosylation modification ofβ-ovomucin,while positive effect on magnum morphology and barrier function could also in part account for the ovomucin content.This would provide a promising research direction on the adoption of nutritional interventions for manipulation of egg white quality from perspectives of albumen protein synthesis. 展开更多
关键词 egg white quality low-gossypol cottonseed meal laying hen OVOMUCIN SERINE
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三维石墨烯基材料的制备、结构与性能 被引量:9
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作者 刘杰 曾渊 +2 位作者 张俊 张海军 刘江昊 《化学进展》 SCIE CAS CSCD 北大核心 2019年第5期667-680,共14页
石墨烯具有单层碳原子组成的六方晶系晶体结构及独特的电学、化学、力学和热学性质。然而,由于石墨烯片层之间较强的π-π键和范德华力,导致易团聚或堆积,使其比表面积大幅减小,严重损害其性能。解决上述问题的最有效方法之一是构建具... 石墨烯具有单层碳原子组成的六方晶系晶体结构及独特的电学、化学、力学和热学性质。然而,由于石墨烯片层之间较强的π-π键和范德华力,导致易团聚或堆积,使其比表面积大幅减小,严重损害其性能。解决上述问题的最有效方法之一是构建具有多孔结构的三维石墨烯基材料,不仅保留了石墨烯优秀的导电性能和力学性能等本征特性,而且获得密度低、比表面积大、孔隙率高等结构优点,进而满足吸附剂、催化剂载体、生物传感器及电池与超级电容器电极材料等先进功能材料领域的应用需要。因此,开发三维石墨烯基材料的先进制备方法成为本领域研究的热点方向。本文综述了三维石墨烯基材料的现有制备方法,包括自组装法(水热还原法、化学还原法及冷冻干燥法)、模板法(胶体模板法、模板辅助化学气相沉积法及模板辅助水热还原法)和3D打印法(直写成型法、喷墨打印法、熔融沉积成型法、光固化成型法、选区激光烧结法及选区激光熔融法),总结了上述方法的优点及当前存在的主要问题,并且对三维石墨烯基材料制备技术的发展方向进行了展望。 展开更多
关键词 三维石墨烯基材料 多孔材料 制备 3D 打印 超级电容器
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Key technologies for networking in satellite-terrestrial integrated network
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作者 haijun zhang Sichen LU Xiaoqi zhang 《Chinese Journal of Aeronautics》 2025年第9期267-270,共4页
1.Introduction As a key development of the next-generation spatial information infrastructure,1the Satellite-Terrestrial Integrated Network(STIN)has become a strategic priority actively pursued by major spacefaring na... 1.Introduction As a key development of the next-generation spatial information infrastructure,1the Satellite-Terrestrial Integrated Network(STIN)has become a strategic priority actively pursued by major spacefaring nations and regions,including the United States,Europe,China,and Russia.Specifically,Space X’s Starlink project has deployed over 6750 satellites,2while One Web has completed its initial phase of satellite constellation deployment with more than 600 satellites. 展开更多
关键词 satellite terrestrial integrated network satellite constellation starlink project next generation spatial information infrastructure Starlink OneWeb STIN
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Phytobiotics in poultry:revolutionizing broiler chicken nutrition with plant‑derived gut health enhancers
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作者 Uchechukwu Edna Obianwuna Xinyu Chang +4 位作者 Vivian U.Oleforuh‑Okoleh Patience N.Onu haijun zhang Kai Qiu Shugeng Wu 《Journal of Animal Science and Biotechnology》 2025年第1期1-33,共33页
As the global population continues to expand,the demand for broiler chicken production to supply safe and high-quality meat is increasing.To meet this ever-growing demand,broiler chickens with enhanced growth performa... As the global population continues to expand,the demand for broiler chicken production to supply safe and high-quality meat is increasing.To meet this ever-growing demand,broiler chickens with enhanced growth performance are being developed,but they often face challenges related to oxidative stress,which can adversely affect gut health.Phytobiotics,which are plant-derived feed additives known for their antimicrobial,antioxidant,immune-modulating,and growth-promoting properties,have emerged as promising natural alternatives to synthetic antibiotics.This review consolidates recent advancements in the use of phytobiotics-derived products from leaves,roots,seeds,flowers,and their extracts in broiler diets reared under standard experimental conditions,without the introduction of stressors.The focus is on elucidating the key mechanisms through which phytobiotics improve gut health,includ-ing their effects on gut morphology,integrity,microflora composition,antioxidant capacity,and immune function.The review highlights the potential of phytobiotics to revolutionize broiler nutrition by acting as natural enhancers of gut health.Research findings reveal that phytobiotics significantly improve intestinal health,and boost growth per-formance,offering a sustainable approach to managing to gut dysfunction.These findings indicate a potential shift in how gut-health related challenges in broilers can be addressed,moving towards natural phytobiotic therapy.How-ever,several challenges persist.Optimizing the dosage of phytobiotics,ensuring consistent performance,and over-coming the limitations related to their extraction and application are key areas requiring further investigation.The review emphasizes the importance of continued research to refine phytobiotic formulations,explore synergistic effects,and incorporate advanced technologies such as AI-driven methods and precision nutrition to tailor feeding strategies more effectively.Additionally,the development of innovative delivery systems,such as nanoencapsula-tion,is suggested as a way to enhance the effectiveness and reliability of phytobiotics.By highlighting the potential of phytobiotics to revolutionize broiler nutrition,this review supports the poultry industry’s shift towards antibiotic-free and sustainable dietary solutions,offering new perspectives on the future of broiler chicken production. 展开更多
关键词 BROILERS Essential oils Gut health Herbs and spices Phytobiotics Plant extracts
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High-toughness Zn-Mn-Ca alloys as potential materials for intestinal implants
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作者 Xiao-Jing Ji Kun Yang +5 位作者 Sheng-Lian Yao haijun zhang Ke-Wei Gao zhang-Zhi Shi Dake Xu Lu-Ning Wang 《Journal of Materials Science & Technology》 2025年第34期20-37,共18页
There have been many studies on the perspective Zn alloys for bone implants,but few for intestinal applications.Zn-0.4Mn-x Ca(x=0,0.05 and 0.1 wt.%)alloys are developed in this work for intestinal applications,in orde... There have been many studies on the perspective Zn alloys for bone implants,but few for intestinal applications.Zn-0.4Mn-x Ca(x=0,0.05 and 0.1 wt.%)alloys are developed in this work for intestinal applications,in order to make use of proliferation effects of Mn and Ca elements on intestinal probiotics and epithelial cells.Rat small intestinal crypt epithelial(IEC-6)cells can grow healthily on surfaces of all the alloys.Among them,the number of healthy cells on Zn-0.4Mn-0.1Ca is the largest.IEC-6 cell vi-ability is over 160%(much higher than the benchmark of 75%)in 20%-100%extracts of Zn-0.4Mn-0.1Ca for 5 d.All the alloys can promote proliferation of L.acidophilus(intestinal probiotic)and inhibit growth of Escherichia coli(intestinal pathogen).Among them,Zn-0.4Mn-0.1Ca alloy possesses the greatest effect.With the increase of Ca content,the strength of the alloy increases.Zn-0.4Mn-0.1Ca alloy has the highest strength and good plasticity among the three alloys.It exhibits a yield strength of 252 MPa,an ultimate tensile strength of 288 MPa,and a elongation to failure of 41%.Since CaZn_(13)-MnZn_(13)-Zn micro-cell con-trols corrosion rate,Zn-0.4Mn-0.1Ca with the highest volume fractions of MnZn_(13)and CaZn_(13)has the highest corrosion rate of 17.64μm/year when immersed in simulated intestinal fluid for 28 d.Overall,the Zn-Mn-Ca alloys are promising candidates for intestinal implants. 展开更多
关键词 Biodegradable Zn alloys Intestinal applications CYTOCOMPATIBILITY Bacterial activity Corrosion behavior
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Joint optimization of UAV aided covert edge computing via a deep reinforcement learning framework
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作者 Wei WEI Shu FU +2 位作者 Yujie TANG Yuan WU haijun zhang 《Chinese Journal of Aeronautics》 2025年第10期96-106,共11页
In this work,we consider an Unmanned Aerial Vehicle(UAV)aided covert edge computing architecture,where multiple sensors are scattered with a certain distance on the ground.The sensor can implement several computation ... In this work,we consider an Unmanned Aerial Vehicle(UAV)aided covert edge computing architecture,where multiple sensors are scattered with a certain distance on the ground.The sensor can implement several computation tasks.In an emergency scenario,the computational capabilities of sensors are often limited,as seen in vehicular networks or Internet of Things(IoT)networks.The UAV can be utilized to undertake parts of the computation tasks,i.e.,edge computing.While various studies have advanced the performance of UAV-based edge computing systems,the security of wireless transmission in future 6G networks is becoming increasingly crucial due to its inherent broadcast nature,yet it has not received adequate attention.In this paper,we improve the covert performance in a UAV aided edge computing system.Parts of the computation tasks of multiple ground sensors are offloaded to the UAV,where the sensors offload the computing tasks to the UAV,and Willie around detects the transmissions.The transmit power of sensors,the offloading proportions of sensors and the hovering height of the UAV affect the system covert performance,we propose a deep reinforcement learning framework to jointly optimize them.The proposed algorithm minimizes the system average task processing delay while guaranteeing that the transmissions of sensors are not detected by the Willie under the covertness constraint.Extensive simulations are conducted to verify the effectiveness of the proposed algorithm to decrease the average task processing delay with comparison with other algorithms. 展开更多
关键词 Covert communication Unmanned aerial vehicle Edge computing Joint optimization Deep reinforcement
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Construction of hollow porous lychee-structured Ni/C/ZnFe_(2)O_(4) microwave-responsive catalysts with rapid efficiently reduction of Cr(VI)ions
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作者 Gaoqian Yuan Ling zhang +6 位作者 Jingzhe zhang Long Dong Xuefeng Liu Yage Li Liang Huang Faliang Li haijun zhang 《Green Energy & Environment》 2025年第10期2086-2096,共11页
Designing catalysts with high reaction efficiency is essential for reducing heavy metal Cr(VI)ions in wastewater via microwave induction.In this paper,a unique microwave-responsive lychee-like Ni/C/ZnFe_(2)O_(4) compo... Designing catalysts with high reaction efficiency is essential for reducing heavy metal Cr(VI)ions in wastewater via microwave induction.In this paper,a unique microwave-responsive lychee-like Ni/C/ZnFe_(2)O_(4) composite catalyst with a double-shell hollow porous heterojunction structure was constructed for the efficient reduction of Cr(VI).Benefiting from the novel hollow porous structure and“carbon nanocage”structure of the Ni/C/ZnFe_(2)O_(4),coupled with excellent electromagnetic wave absorption ability,the prepared lychee-like Ni/C/ZnFe_(2)O_(4) com-posite catalyst could remove up to 98%of Cr(VI)(50 mg L 1,50 mL)after 40 min of microwave irradiation,even in nearly neutral water conditions.Additionally,density functional theory calculations indicated that the heterojunction interface between Ni/C and ZnFe_(2)O_(4) enhances electron transfer from ZnFe_(2)O_(4) to Ni/C,ultimately facilitating the removal of Cr(VI).Furthermore,the incorporation of Ni/C facilitated the 2 acceleration of H ion transfer to*Cr_(2)O_(7),thereby expediting the conversion kinetics of the latter.This research aims to establish a theoretical and experimental foundation for the effective and stable microwave-assisted catalytic reduction of heavy metal Cr(VI)ions,presenting new insights and methods to combat heavy metal contamination. 展开更多
关键词 Microwave-assisted catalysis Cr(VI)reduction Ni/C/ZnFe_(2)O_(4) DFT calculation
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Laser-thermal reduction synthesis of high-entropy alloys towards high-performance pH universal hydrogen evolution reaction
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作者 Yingjie Yu Qi Wang +6 位作者 Xiaohan Li Qiao Xie Ke Xu Shaowei zhang haijun zhang Mingxing Gong Wen Lei 《Nano Materials Science》 2025年第3期400-408,共9页
Owing to their multi-elemental compositions and unique high-entropy mixing states,high-entropy alloy(HEA)nanoparticles(NPs)displaying tunable activities and enhanced stabilities thus have become a rapidly growing area... Owing to their multi-elemental compositions and unique high-entropy mixing states,high-entropy alloy(HEA)nanoparticles(NPs)displaying tunable activities and enhanced stabilities thus have become a rapidly growing area of research in recent years.However,the integration of multiple elements into HEA NPs at the nanoscale remains a formidable challenge,especially when it comes to the precise control of particle size,elemental composition and content.Herein,a simple and universal high-energy laser assisted reduction approach is presented,which achieves the preparation of HEA NPs with a wide range of multi-component,controllable particle sizes and constitution on different substrates within seconds.Laser on carbon nanofibers induced momentary high-temperature annealing(>2000 K and ramping/cooling rates>10^(5)K s^(-1))to successfully decorate HEA NPs up to twenty elements with excellent compatibility for large-scale synthesis(20.0×20.0 cm^(2)of carbon cloth).The IrPdPtRhRu exhibit robust electrocatalytic hydrogen evolution reaction(HER)activities and low overpotentials of 16,28,and 12 mV at a current density of 10 mA cm^(-2)in alkaline(1.0 M KOH),alkaline simulated seawater(1.0 M KOH+0.5 M NaCl),and acidic(0.5 M H_(2)SO_(4))electrolytes,respectively,and excellent stability(7 days and>2000 cycles)at the alkaline HER. 展开更多
关键词 High-entropy alloy nanoparticle Laser assisted reduction Hydrogen production
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Hierarchical Representations Feature Deep Learning for Face Recognition
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作者 haijun zhang Yinghui Chen 《Journal of Data Analysis and Information Processing》 2020年第3期195-227,共33页
Most modern face recognition and classification systems mainly rely on hand-crafted image feature descriptors. In this paper, we propose a novel deep learning algorithm combining unsupervised and supervised learning n... Most modern face recognition and classification systems mainly rely on hand-crafted image feature descriptors. In this paper, we propose a novel deep learning algorithm combining unsupervised and supervised learning named deep belief network embedded with Softmax regress (DBNESR) as a natural source for obtaining additional, complementary hierarchical representations, which helps to relieve us from the complicated hand-crafted feature-design step. DBNESR first learns hierarchical representations of feature by greedy layer-wise unsupervised learning in a feed-forward (bottom-up) and back-forward (top-down) manner and then makes more efficient recognition with Softmax regress by supervised learning. As a comparison with the algorithms only based on supervised learning, we again propose and design many kinds of classifiers: BP, HBPNNs, RBF, HRBFNNs, SVM and multiple classification decision fusion classifier (MCDFC)—hybrid HBPNNs-HRBFNNs-SVM classifier. The conducted experiments validate: Firstly, the proposed DBNESR is optimal for face recognition with the highest and most stable recognition rates;second, the algorithm combining unsupervised and supervised learning has better effect than all supervised learning algorithms;third, hybrid neural networks have better effect than single model neural network;fourth, the average recognition rate and variance of these algorithms in order of the largest to the smallest are respectively shown as DBNESR, MCDFC, SVM, HRBFNNs, RBF, HBPNNs, BP and BP, RBF, HBPNNs, HRBFNNs, SVM, MCDFC, DBNESR;at last, it reflects hierarchical representations of feature by DBNESR in terms of its capability of modeling hard artificial intelligent tasks. 展开更多
关键词 Face Recognition UNSUPERVISED Hierarchical Representations Hybrid Neural Networks RBM Deep Belief Network Deep Learning
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非洲猪瘟疫情背景下我国生猪保险发展现状、功能作用及对策建议探讨 被引量:5
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作者 刘婧 张海军 +2 位作者 吕倩 王熙 吴昊 《猪业科学》 2020年第11期116-119,共4页
生猪产业是农业生产的重要组成部分,是农民收入的重要来源之一,猪肉也是我国城乡居民的主要副食品。2018年8月,我国暴发非洲猪瘟疫情,非洲猪瘟对我国生猪产业造成了较大影响,猪肉产能迅速下降,猪肉价格持续上涨。发展生猪保险,是落实国... 生猪产业是农业生产的重要组成部分,是农民收入的重要来源之一,猪肉也是我国城乡居民的主要副食品。2018年8月,我国暴发非洲猪瘟疫情,非洲猪瘟对我国生猪产业造成了较大影响,猪肉产能迅速下降,猪肉价格持续上涨。发展生猪保险,是落实国家扶持生猪生产政策的重要举措,有利于帮助农户分散转移风险,调动养猪积极性,推动农民增收;有利于提高生猪产业防灾防疫能力,稳定生猪市场供应,保障人民生活;有利于充分发挥保险的社会管理功能,助力国家乡村振兴战略。文章首先简要介绍了我国生猪保险业务发展现状,包括业务规模、保险产品情况及存在问题等,在此基础上结合生产实际情况,对非洲猪瘟背景下我国生猪保险对生猪稳产保供的功能作用进行了详细分析,包括经济补偿、价格稳定、风险管理、融资增信、社会治理和产业扶贫等六大方面。虽然我国生猪保险业务发展取得了较好成效,但仍面临着业务覆盖率偏低、道德风险高、市场化保费费率定价缺乏等难题,所以文章在最后提出了推进我国生猪保险稳定健康发展的相关建议。 展开更多
关键词 生猪保险 非洲猪瘟 产品创新 功能作用 对策建议
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三种方法对结球白菜种子精选效果比较 被引量:1
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作者 吴萍 宋顺华 +4 位作者 张凤兰 余阳俊 李丽 张海军 丁海凤 《农业科学》 2017年第8期586-593,共8页
结球白菜种子分别进行坡选、筛选和色选,对精选后不同类别的种子进行重量测定、发芽试验、幼苗特性分析和抗老化处理。试验结果表明,不同类别的种子在千粒重、发芽特性、幼苗特性和抗老化能力方面存在明显差异。通过坡选加筛选的方法,... 结球白菜种子分别进行坡选、筛选和色选,对精选后不同类别的种子进行重量测定、发芽试验、幼苗特性分析和抗老化处理。试验结果表明,不同类别的种子在千粒重、发芽特性、幼苗特性和抗老化能力方面存在明显差异。通过坡选加筛选的方法,去除种子批中25.1%的种子,可以提高剩余活力种子和萌发整齐度。 展开更多
关键词 种子精选 结球白菜 种子 发芽 幼苗
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超亲水疏油材料的制备及其油水分离性能 被引量:6
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作者 李孝建 张海军 +3 位作者 李赛赛 张俊 贾全利 张少伟 《化学进展》 SCIE CAS CSCD 北大核心 2020年第6期851-860,共10页
含油污水的随意排放对海洋、沿海周边环境以及人类健康造成了严重的影响。传统的油水分离方法易造成环境二次污染,同时也是对有限资源的一种损耗。因此,如何高效环保地解决含油污水问题具有重要意义。物理过滤/吸附法被认为是一种高效... 含油污水的随意排放对海洋、沿海周边环境以及人类健康造成了严重的影响。传统的油水分离方法易造成环境二次污染,同时也是对有限资源的一种损耗。因此,如何高效环保地解决含油污水问题具有重要意义。物理过滤/吸附法被认为是一种高效环保的分离方法,基于仿生学原理,许多可用于物理选择性分离的超亲油疏水和超亲水疏油材料被制备出来。超亲油疏水材料易被油污染,重复利用率低;相比之下,超亲水疏油材料具有自清洁性且重复利用率高,在油水分离方面具有广阔的应用前景。根据基底材料的选择不同,本文综述了金属基以及高分子基超亲水疏油材料的研究现状,总结了其优缺点,并对今后超亲水疏油材料的研究方向和重点进行了展望。 展开更多
关键词 油水分离材料 超亲水 疏油 微纳米结构
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储能硝酸熔盐的热稳定性分析 被引量:2
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作者 胡憧憬 孙泽 +3 位作者 黄龙 张海军 宋兴福 于建国 《过程工程学报》 CAS CSCD 北大核心 2018年第6期1315-1322,共8页
研究了商业化储能二元混合硝酸熔盐Solar salt(60%NaNO3-40%KNO3)的热稳定性和恒温热稳定性,采用热重法分析了其热分解温度,通过恒温实验考察了处于开放空气气氛中的NaNO3,KNO3和Solar salt在不同温度下的热稳定性,研究了NaNO3和KNO3在S... 研究了商业化储能二元混合硝酸熔盐Solar salt(60%NaNO3-40%KNO3)的热稳定性和恒温热稳定性,采用热重法分析了其热分解温度,通过恒温实验考察了处于开放空气气氛中的NaNO3,KNO3和Solar salt在不同温度下的热稳定性,研究了NaNO3和KNO3在Solar salt高温不稳定性中的作用.结果表明,大于500℃时温度越高,熔盐越不稳定,相同温度下不稳定程度NaNO3>Solar salt>KNO3.温度升高,分解产物NO2-平衡含量增大而达到平衡的时间缩短,O^2-含量很低.Solar salt中硝酸盐热分解和挥发的质量损失比接近1:1,NaNO3是造成体系热分解的主要原因,而KNO3起到抗挥发的作用. 展开更多
关键词 硝酸熔盐 热稳定性 质量损失 机理 热分解 挥发
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耐高温隔热氧化物气凝胶研究进展 被引量:4
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作者 许晴 王昕悦 +3 位作者 蔡伟杰 段红娟 张海军 李少平 《化学进展》 SCIE CAS CSCD 北大核心 2024年第10期1520-1540,共21页
氧化物气凝胶是一种三维纳米多孔材料,具有高孔隙率、高比表面积、低热导率及高熔点等优点,表现出了优异的耐高温以及隔热性能。本文综述了氧化硅、氧化铝、氧化锆气凝胶、二元和多元耐高温隔热氧化物气凝胶及其复合气凝胶的研究进展,... 氧化物气凝胶是一种三维纳米多孔材料,具有高孔隙率、高比表面积、低热导率及高熔点等优点,表现出了优异的耐高温以及隔热性能。本文综述了氧化硅、氧化铝、氧化锆气凝胶、二元和多元耐高温隔热氧化物气凝胶及其复合气凝胶的研究进展,总结了氧化物气凝胶的制备方法和性能,提出了其中存在的问题,并对氧化物气凝胶在耐高温隔热领域的应用进行了展望。 展开更多
关键词 氧化物气凝胶 耐高温 隔热
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