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Dynamics of cadmium and arsenic in the soil-rice system:Insights from different forms manganese fertilizer application
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作者 Tianyi Yan Quan Zhang +7 位作者 Haifei Chen Jingheng Zhou Qiren Wen Bo Li Qihong Zhu Daoyou Huang Chao Xu Hanhua Zhu 《Journal of Environmental Sciences》 2026年第2期253-263,共11页
Manganese(Mn)is widely used to control cadmium(Cd)and arsenic(As)uptake by rice,but the effects of different Mn forms and concentrations on Cd/As movement in the soil-rice system are unclear.The study investigated the... Manganese(Mn)is widely used to control cadmium(Cd)and arsenic(As)uptake by rice,but the effects of different Mn forms and concentrations on Cd/As movement in the soil-rice system are unclear.The study investigated the mechanisms by which three Mn compounds affected the accumulation of Cd/As in rice under different application rates.MnO2,MnSO4,and MnCO_(3) treatments significantly reduced grains Cd levels by 27.6%,30.2%,and 28.1%,respectively,while As levels were less consistently affected.Three forms of Mn fertilizers enhanced the conversion of exchangeable to carbonate bound-Cd,which closely related to the increase of soil pH.MnO_(2) and MnCO_(3) reduced Cd translocation by increasing Cd/As adsorption on iron plaques,and MnSO4 and MnCO_(3) decreased Cd translocation by boosting root SOD and Cys levels.Transcriptome analysis revealed that Mn^(2+) upregulated genes involved in the antioxidant defense system,limited Cd transport by enhancing OsABCC1 and OsHMA3 expression,and promoted As translocation by increasing OsLsi2 expression.Overall,different forms of Mn fertilizers effectively reduced Cd toxicity by fixing Cd in soil carbonate and iron plaques,and restricting Cd transport.Although Mn fertilizers reduced As availability in soil and affected As absorption in rice,they have certain limitations and need to be further explored.These findings reveal the mechanism by which different forms of Mn regulate the fixation and migration behavior of Cd and As,providing new ideas and theoretical basis for reducing the environmental risk of Cd and As. 展开更多
关键词 Manganese forms CADMIUM ARSENIC Iron plaques BIOAVAILABILITY TRANSCRIPTOMIC
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Form and load transfer aspects of foundation systems:Case-based implementation and adaptation for buildings
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作者 Abolfazl Eslami Amirhossein Ebrahimipour +2 位作者 Meysam Imani Reza Imam Pinqiang Mo 《Deep Underground Science and Engineering》 2026年第1期176-192,共17页
Conventionally,foundations have been classified as shallow or deep in routine civil engineering practice.However,due to recent developments,two other approaches,semi-deep and ground modification foundations,are now av... Conventionally,foundations have been classified as shallow or deep in routine civil engineering practice.However,due to recent developments,two other approaches,semi-deep and ground modification foundations,are now available,complicating foundation categorization.Accordingly,a new concept for foundation categorization is introduced in this paper based on insights into the theory of structure analysis.Based on the form aspect,foundation systems can be categorized as one-dimensional(linear),two-dimensional(planar),and threedimensional(volumetric).Based on the load transfer aspect,foundations can also be categorized as vector-acting(piles),section or surface-acting(rafts and shells),and block-acting(piled rafts).As a step toward implementing this new categorization scheme,a database of 22 cases has been compiled,symbolizing novel introduced foundation systems.This compilation involves structures such as offshore jackets,high-rise buildings,towers and storages,and diverse geomaterials.Among them,a few have been selected for detailed evaluation,emphasizing influential factors in foundation selection,comprising superstructure,subsoil condition,foundation system,circumferential conditions,and supplementary considerations,that is,constructional and sustainability-based issues.Lessons learned from experience and these knowledge-based cases have described for foundation selection and implementation.Geotechnical and practical aspects with critical components have been realized as major performance assessment and comparison factors.Foundation systems have been compared and ranked using the improved analytic hierarchy process approach.Finally,four categories of buildings,from low-rise to towers and four prevailing levels of soil strength,from soft to very hard,have been considered to propose a perspective for building substructure implementation,adapted via relevant cases.Overall,the introduced categorization is recognized as an efficient algorithm for the experimentation of appropriate foundations for specific structures and subsoil conditions. 展开更多
关键词 case-based adaptation FORM foundation system load transfer underground substructure
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Impact hydroforming characteristics for a half-tube part with curvature
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作者 Hongliang ZHU Yong XU +5 位作者 Boris B.KHINA Wenlong XIE Shi-Hong ZHANG Liangliang XIA Mingyu GAO Artur I.POKROVSKY 《Chinese Journal of Aeronautics》 2026年第1期626-642,共17页
Taking half-tube part with curvature as an example,the Impact Hydroforming(IHF)characteristics were studied by combining the actual forming experiment and numerical simulation.The IHF experiment showed that wrinkles a... Taking half-tube part with curvature as an example,the Impact Hydroforming(IHF)characteristics were studied by combining the actual forming experiment and numerical simulation.The IHF experiment showed that wrinkles appeared at the bottom of the part during single-step forming,but no wrinkles were observed during double-step forming.The thinning rate and deviation of the wall thickness of the part in each area were less than 20%and 2.7 mm,correspondingly,and the drawing depth of the part reached 45.8 mm.The effect of double-step forming was better than that of single-step forming,which was related to the IHF forming law.Besides,the characteristics of the IHF process were studied by numerical simulation.The results indicated that when double-step forming was utilized,there was almost no velocity field in the opposite direction of deformation after the bottom of the part contacted the die,and the existence of stress state at the bottom would restrain and eliminate the wrinkles.The inertia effect evolved with the driving pressure.Specially,the inertia effect can improve the flow of metal and reduce the deviation of the wall thickness of the part under double-step forming. 展开更多
关键词 Aluminum-lithium alloy Forming characteristics Half-tube part Impact hydroforming Inertia effect
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EXCERPTS FROM MAJOR CHINESE MAGAZINES
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《ChinAfrica》 2026年第1期7-7,共1页
RENEWING THE FORBIDDEN CITY’S CENTURY-OLD LEGACY.Oriental Outlook.27 November 2025.At sunrise,the Forbidden City glows under a veil of gold;at night,it retreats into quiet dignity.But the palace never really sleeps.A... RENEWING THE FORBIDDEN CITY’S CENTURY-OLD LEGACY.Oriental Outlook.27 November 2025.At sunrise,the Forbidden City glows under a veil of gold;at night,it retreats into quiet dignity.But the palace never really sleeps.As visitors depart,the“digital relic vault”awakens online,where porcelain,calligraphy,jade and timepieces reveal their beauty in virtual form.History continues to breathe in the data stream. 展开更多
关键词 virtual form digital relic vault PORCELAIN Forbidden City timepieces CALLIGRAPHY data stream JADE
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Multi-pass intermittent local loading process of large-scale rib-web component:Forming characteristics and implementing apparatus
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作者 Dawei ZHANG Peng DONG +2 位作者 Jingxiang LI Zijian YU Shengdun ZHAO 《Chinese Journal of Aeronautics》 2026年第1期601-625,共25页
The multi-pass intermittent local loading process,which features a more flexible processing path,can further enhance the second material distribution during local loading,improve the formability of components,and redu... The multi-pass intermittent local loading process,which features a more flexible processing path,can further enhance the second material distribution during local loading,improve the formability of components,and reduce forming loads.However,the absence of compatible forming equipment makes it difficult to control the constraint in the unloaded zones during the forming process.This difficulty complicates coordination and control of deformation,particularly for asymmetric rib-web components.Additionally,the current implementation involves multi-fire heating,a long process flow,and high energy consumption,which limits the popularization and application of the local loading process.In this study,a new multi-pass local loading hydraulic forming apparatus that can quickly and reliably switch between heavy-load deformation and low-load constraint for different local loading sub-dies was developed.A 10-tonne laboratory prototype was developed,and the forming characteristics during the forming process as well as the response characteristics of the hydraulic system during the multi-pass intermittent local loading of rib-web component were investigated using numerical simulations and physical experiments.Results indicated that,compared to a whole loading process with the same initial geometry of billet,the total forming load(i.e.,the sum of loaded and restrained loads)is reduced by more than 40%with the local loading process,and by nearly 50%with multi-pass local loading.The multi-pass local loading process allows for more effective control of material flow compared to single-pass local loading,leading to improved cavity filling and reduced flow line disturbance.For a large-scale,complex titanium alloy bulkhead,the cavity filling problem was addressed by optimizing the multi-pass local loading path with an unequal thickness billet.The dynamic performance of the multi-pass local loading hydraulic system was found to be robust,with stable pressure transitions during motion and load switching for the sub-die(s).The dynamic characteristic of the hydraulic cylinder when switching from non-moving/unloaded state to a moving/loading state are consistent whether a load is present or not.However,the dynamic characteristics differ when switching from a moving/loading state to non-moving/unloaded state,showing opposite behavior.The developed hydraulic drive mechanism provides a way for implementation of multi-pass local loading without auxiliary operation and extra heating.The results of the study provide a foundation for the industrial production of large-scale,complex components with reduced force requirement and low-energy consumption. 展开更多
关键词 Forming characteristics Hydraulic system Intermittent local loading process Material flow Rib-web component
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λ-BIHARMONIC HYPERSURFACES IN 6-DIMENSIONAL PSEUDO-RIEMANNIAN SPACE FORMS
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作者 DUAN Zhen-ping YANG Chao +1 位作者 LIU Jian-cheng CHEN Jia-rui 《数学杂志》 2026年第1期1-19,共19页
In this paper,we studyλ-biharmonic hypersurfaces M_(r)^(5) of 6-dimensional pseudo Riemannian space form N_(p)^(6)(c)with the indexs 0≤p≤6,r=p−1 or p,and constant curvature c.It was proved that if the shape operato... In this paper,we studyλ-biharmonic hypersurfaces M_(r)^(5) of 6-dimensional pseudo Riemannian space form N_(p)^(6)(c)with the indexs 0≤p≤6,r=p−1 or p,and constant curvature c.It was proved that if the shape operator of M_(r)^(5) is diagonalizable,then the mean curvature is a constant.As an application,we find some types of biharmonic hypersurfaces of N_(p)^(6)(c)are minimal. 展开更多
关键词 λ-biharmonic hypersurface pseudo-Riemannian space form constant mean curvature shape operator minimal
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Corrosion fatigue mechanisms and control technologies in aviation aluminum alloys:A critical review
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作者 Yuqiang CHEN Zimin HE +5 位作者 Heng LI Dingding LU Yufeng SONG Lihua ZHAN Suping PAN Wenhui LIU 《Chinese Journal of Aeronautics》 2026年第2期531-563,共33页
Aviation aluminum alloys,primarily from the Al-Cu,Al-Zn-Mg-(Cu),and Al-Li series,have been widely applied over six decades,greatly advancing the aviation industry.However,their Corrosion Fatigue(CF)properties impede f... Aviation aluminum alloys,primarily from the Al-Cu,Al-Zn-Mg-(Cu),and Al-Li series,have been widely applied over six decades,greatly advancing the aviation industry.However,their Corrosion Fatigue(CF)properties impede further advancements,prompting extensive research into their CF behaviors and underlying mechanisms.This review comprehensively evaluates previous studies on their development history,CF mechanisms,and key influencing factors.First,the historical evolution of aerospace aluminum alloys is summarized.Then,the currently recognized four crack initiation mechanisms and three crack propagation mechanisms are concluded,and the effects of external and internal factors on CF performance are discussed.The paper also reviews three methods and CF life prediction models for characterizing the CF behavior of aerospace aluminum alloys.Most existing studies on the CF behavior of aluminum alloys are based on the single corrosive environment,neglecting the fact that aircrafts experience multiple corrosive environments during service.However,the most critical scientific challenge is how to enhance their CF properties under increasingly demanding service conditions.For the purpose,this paper introduces advanced forming techniques based on the microstructural control,such as Equal Channel Angular Pressing(ECAP)and High-Pressure Torsion(HPT),aimed at laying the theoretical foundation for improving CF properties through microstructural regulation. 展开更多
关键词 Aviation aluminum alloys CF characterization Corrosion fatigue Forming technologies Influencing factors Life prediction models
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全彩电子纸广告应用场景高色彩饱和度研究
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作者 吕启宏 《信息技术与标准化》 2026年第3期37-41,共5页
为了实现Spectra 6全彩模组13.3英寸(13.3英寸≈33.78 cm)及以上大尺寸产品在广告场景的落地应用,通过提升微杯粒子的显示饱和度满足商业宣传内容的全彩呈现需求,提出以波形(Wave Form)调试技术为核心的全彩高饱和度显示实现方案。分析... 为了实现Spectra 6全彩模组13.3英寸(13.3英寸≈33.78 cm)及以上大尺寸产品在广告场景的落地应用,通过提升微杯粒子的显示饱和度满足商业宣传内容的全彩呈现需求,提出以波形(Wave Form)调试技术为核心的全彩高饱和度显示实现方案。分析该方案需以Spectra 3100四色产品的Wave Form调试技术为基础进行延伸拓展,阐述了针对13.3英寸(13.3英寸≈33.78 cm)以上大尺寸全彩电子纸的黑、白、红、黄、蓝、绿六大色调开展专项调试的具体方向,强调了蓝色与绿色高饱和度表现对丰富广告内容全彩展现效果的关键作用,从而推动Spectra 6全彩模组高饱和、精细化的色彩显示在广告场景下的成功应用。 展开更多
关键词 微杯粒子 Wave Form调试 高饱和度 色调
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Experimental study on damage characteristics of t-shaped stiffened plates subjected to different types of shaped charges:Linear-shaped charge,embowed linear-shaped charge,and embowed linear explosively formed projectile
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作者 Shenhe Zhang Zhifan Zhang +4 位作者 Shuxin Yang Longkan Wang Yutong Sui Guiyong Zhang Zhi Zong 《Defence Technology(防务技术)》 2026年第2期231-243,共13页
In order to investigate the penetration performance of Linear-Shaped Charge(LSC),Embowed LinearShaped Charge(ELSC),and Embowed Linear Explosively Formed Projectile(ELEFP)on T-shaped stiffened plates,a series of near-f... In order to investigate the penetration performance of Linear-Shaped Charge(LSC),Embowed LinearShaped Charge(ELSC),and Embowed Linear Explosively Formed Projectile(ELEFP)on T-shaped stiffened plates,a series of near-field air-burst experiments are conducted.The damage modes and characteristics of the target plates are compared and analyzed.Each flat plate section is completely punctured,resulting in a penetration hole.The damage modes induced by the three charge types on the stiffened plate structure are consistent,characterized by shear failure in the central region of the flat plate due to penetration by the penetrator,localized plastic deformation of the flat plate,and local penetration failure resulting from partial perforation of the central stiffener.The penetration lengths caused by ELSC and ELEFP are 45.1%and 46.1% larger than that of LSC,while the half-width of the penetration hole generated by ELEFP is 54.2% and 24.7% smaller than that of ELSC and LSC,respectively.The penetration height caused by ELEFP are 17.5%and 62.1% larger than that of ELSC and LSC,respectively.The stiffener effectively segments the damage area,enhancing the local structural strength and limiting the extent of plastic deformation in the flat plate section.The comparative results show that the ELSC proves to be more effective for efficient large-scale damage,and ELEFP is more suitable for achieving efficient localized damage. 展开更多
关键词 Linear-shaped charge Embowed linear-shaped charge Embowed linear explosively formed PROJECTILE Near-filed explosion Penetration performance Stiffened plate
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G protein-coupled receptor 37 biomarker potential in Parkinson’s disease:Inflammation might be the hidden trigger
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作者 Josep Argerich Marc López-Cano Francisco Ciruela 《Neural Regeneration Research》 2026年第7期2938-2939,共2页
G protein-coupled receptor 37(GPR37)is an orphan receptor predominantly expressed in the brain,particularly in oligodendrocytes and certain types of neurons.Notably,it has been shown that the N-terminal domain of GPR3... G protein-coupled receptor 37(GPR37)is an orphan receptor predominantly expressed in the brain,particularly in oligodendrocytes and certain types of neurons.Notably,it has been shown that the N-terminal domain of GPR37 undergoes proteolysis under normal physiological conditions,resulting in the formation of cleaved receptor forms and the release of its ectodomain(ecto-GPR37)into the extracellular milieu(Mattila et al.,2021).Importantly,ecto-GPR37 density is increased in cerebrospinal fluid(CSF)of patients suffering from sporadic Parkinson’s disease(PD),together with an abnormal GPR37 processing in post-mortem PD substantia nigra(Moratóet al.,2021;Figure 1A). 展开更多
关键词 g protein coupled receptor neurons INFLAMMATION cleaved receptor forms extracellular milieu mattila cerebrospinal fluid csf Parkinson s disease orphan receptor
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Retrieving rare aurora forms from all-sky images via synthetic-to-real progressive learning
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作者 ZHAI Chaoqiang WANG Qian 《Advances in Polar Science》 2026年第1期70-80,共11页
Fine-scale structures can be observed in small field-of-view(FOV)auroral observations,but they are often overlooked because they appear only sporadically in all-sky observations.Such forms are of great interest becaus... Fine-scale structures can be observed in small field-of-view(FOV)auroral observations,but they are often overlooked because they appear only sporadically in all-sky observations.Such forms are of great interest because they may embody specific magnetosphere-ionosphere coupling processes,reveal localized energy deposition pathways,and provide new insights into cross-scale plasma dynamics and instabilities.However,their limited spatial extent,transient occurrence,and scarcity in wide-FOV observations make systematic investigation challenging.Traditional manual analysis struggles to capture these subtle structures within vast all-sky datasets,while automated detection faces severe data imbalance and morphological ambiguity.To address these challenges,we propose a synthetic-to-real progressive learning framework for cross-FOV retrieval of rare auroral forms.A Generative Adversarial Network(GAN)is employed to perform cross-FOV transformation between unpaired small-FOV images containing rare aurora forms and all-sky images(ASI)without such structures,thereby generating large numbers of synthetic ASI with rare auroral morphology.These synthetic samples are used to train an initial detection model,which subsequently undergoes iterative fine-tuning through feedback-guided learning:The model performs inference on new all-sky data,and the progressively accumulated real detections are incorporated into the training set.Experimental results demonstrate that the proposed method achieves over 92%detection accuracy on ASI,enabling high-precision retrieval of small-scale auroral structures across large-scale observations.This framework provides a scalable and effective approach to rediscovering rare auroral phenomena in continuous all-sky monitoring,offering new opportunities for exploring the fine-scale dynamics of the upper atmosphere. 展开更多
关键词 fine-scale auroral structures rare auroral forms cross-FOV retrieval Generative Adversarial Network(GAN) synthetic-to-real progressive learning feedback-guided learning
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The theoretical shaping and medical transformation of“Shen”in traditional Chinese medicine by Taoist philosophy
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作者 Tong Wu Yi-Han He +4 位作者 Jing-Juan Qi Jia-Hui Wang Chao-Yue Zhang Jing-Yi Lin Hai-Yan Ren 《History and Philosophy of Medicine》 2026年第2期33-40,共8页
“Shen”is one of the core contents in the basic theory of traditional Chinese medicine(TCM).Taoist philosophy plays an important role in promoting the theoretical shaping and medical transformation of“Shen”.Taking ... “Shen”is one of the core contents in the basic theory of traditional Chinese medicine(TCM).Taoist philosophy plays an important role in promoting the theoretical shaping and medical transformation of“Shen”.Taking the medical history as the thread and medical philosophy as the speculative dimension,this paper systematically sorts out the evolutionary trajectory of“Shen”in TCM from supernatural worship to philosophical abstraction,and then to medical embodiment,deeply analyzes the shaping effect of Taoist thought on the theoretical framework of“Shen”,and interprets its contemporary medical value.The research shows that Taoist philosophy provides a cosmological foundation,the core of the interdependence of essence,Qi,blood and Shen,and the guidance of spiritual inward concentration for“Shen”in TCM;Huangdi Neijing(Yellow Emperor’s Internal Classic)deeply integrates Taoist philosophy with medical practice,promoting the medical transformation of“Shen”.Its core ideas of“the unity of nature and man”and“the unity of form and Shen”provide traditional wisdom for modern psychosomatic medicine and systems medicine.The“Shen”theory,for which Taoist philosophy serves as an important intellectual source,is not only a crucial foundation for the inheritance and innovation of TCM theory,but also provides important ideological reference for the holistic development of modern medicine. 展开更多
关键词 “Shen”in TCM Huangdi Neijing Taoist philosophy medical transformation the unity of form and Shen
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Corrosion and Copper Foil Formation Behavior of Laser-Welded Joint and Spin-Formed Materials of Commercially Pure Titanium in H_(2)SO_(4)/CuSO_(4) Electrolyte 被引量:1
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作者 Ren Lina Song Yanfei +4 位作者 Qi Liang Yang Jian Yang Jiadian Lei Xiaowei Zhang Jianxun 《稀有金属材料与工程》 北大核心 2025年第6期1467-1477,共11页
Based on the microstructure characterization,electrochemical impedance spectroscopy,potentiodynamic polarization,and immersion corrosion,this work comparatively analyzed the differences in the electrochemical corrosio... Based on the microstructure characterization,electrochemical impedance spectroscopy,potentiodynamic polarization,and immersion corrosion,this work comparatively analyzed the differences in the electrochemical corrosion morphology and post-foil formation surface morphology of laser beam welded(LBW)sample and spin-formed sample,and compared the corrosion resistance and Cu foil formation ability of two samples in H_(2)SO_(4)/NaCl solution and CuSO_(4) reducing electrolyte.Results show that in H_(2)SO_(4) and NaCl solutions,LBW sample and spin-formed sample exhibit excellent passivation ability and corrosion resistance.Both samples show uniform corrosion morphologies and similar corrosion resistance in the strong acidic solution containing Cl^(-).Meanwhile,the Cu foil formation ability of the welded joint is similar to that of the spin-formed sample,and both samples obtain intact Cu foils with high-quality surfaces and small differences in properties. 展开更多
关键词 Ti cathode laser beam welding spin forming CORROSION Cu foil electroplating
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新型耐热合金SP2215无缝管二辊斜轧穿孔的数值模拟
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作者 梁凯 姚志浩 +4 位作者 谢锡善 王洪瑛 程健 代卫星 董建新 《特殊钢》 2025年第4期107-121,I0006,共16页
奥氏体耐热合金在斜轧穿孔过程中工艺参数的选择不当,可能导致毛管出现晶粒粗大、混晶等现象,甚至在加工过程中发生断裂,进而影响到后续的加工变形及产品的最终性能。基于先前的热变形试验,建立SP2215合金的材料模型,并利用有限元软件Si... 奥氏体耐热合金在斜轧穿孔过程中工艺参数的选择不当,可能导致毛管出现晶粒粗大、混晶等现象,甚至在加工过程中发生断裂,进而影响到后续的加工变形及产品的最终性能。基于先前的热变形试验,建立SP2215合金的材料模型,并利用有限元软件Simufact Forming 16.0对合金的斜轧穿孔过程进行模拟,分析了穿孔过程中管坯金属流动、应变场、应力场、应变速率场、温度场及穿孔机穿孔作用力的动态变化,模拟结果与实际变形规律相符。进而探讨了顶伸量、轧辊转速、管坯初始温度等工艺参数对合金热穿孔行为与微观组织的影响,最终获得合金的最佳斜轧穿孔工艺为:顶伸量50 mm、轧辊间距95.84 mm、导板间距116.06 mm、轧辊转速50 r/min、管坯初始温度1100~1150℃。 展开更多
关键词 SP2215合金 斜轧穿孔 Simufact Forming 有限元模拟
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Distribution,species richness,and relative importance of different plant life forms across drylands in China 被引量:2
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作者 Shuran Yao Weigang Hu +16 位作者 Mingfei Ji Abraham Allan Degen Qiajun Du Muhammad Adnan Akram Yuan Sun Ying Sun Yan Deng Longwei Dong Haiyang Gong Qingqing Hou Shubin Xie Xiaoting Wang Jinzhi Ran Bernhard Schmid Qinfeng Guo Karl J.Niklas Jianming Deng 《Plant Diversity》 2025年第2期273-281,共9页
Studies on plant diversity are usually based on the total number of species in a community.However,few studies have examined species richness(SR)of different plant life forms in a community along largescale environmen... Studies on plant diversity are usually based on the total number of species in a community.However,few studies have examined species richness(SR)of different plant life forms in a community along largescale environmental gradients.Particularly,the relative importance(RIV)of different plant life forms in a community and how they vary with environmental variables are still unclear.To fill these gaps,we determined plant diversity of ephemeral plants,annual herbs,perennial herbs,and woody plants from 187 sites across drylands in China.The SR patterns of herbaceous plants,especially perennial herbs,and their RIV in plant communities increased with increasing precipitation and soil nutrient content;however,the RIV of annual herbs was not altered along these gradients.The SR and RIV of ephemeral plants were affected mainly by precipitation seasonality.The SR of woody plants had a unimodal relationship with air temperature and exhibited the highest RIV and SR percentage in plant communities under the harshest environments.An obvious shift emerged in plant community composition,SR and their critical impact factors at 238.5 mm of mean annual precipitation(MAP).In mesic regions(>238.5 mm),herbs were the dominant species,and the SR displayed a relatively slow decreasing rate with increasing aridity,which was mediated mainly by MAP and soil nutrients.In arid regions(<238.5 mm),woody plants were the dominant species,and the SR displayed a relatively fast decreasing rate with increasing aridity,which was mediated mainly by climate variables,especially precipitation.Our findings highlight the importance of comparative life form studies in community structure and biodiversity,as their responses to gradients differed substantially on a large scale. 展开更多
关键词 DRYLANDS Environmental gradients Plant life forms Relative importance Species richness THRESHOLD
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基于Robot Studio的工业机器人远程监控系统设计与研究 被引量:2
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作者 胡辰 《现代信息科技》 2025年第4期193-198,共6页
当前,工业自动化技术进步推动了对工业机器人远程监控与管理需求的增长。为此,设计并实现了一个基于客户端到服务器架构的局域网远程监控系统。利用Robot Studio构建虚拟工作站模拟工业场景,结合PC SDK与Win Form技术开发控制端。系统... 当前,工业自动化技术进步推动了对工业机器人远程监控与管理需求的增长。为此,设计并实现了一个基于客户端到服务器架构的局域网远程监控系统。利用Robot Studio构建虚拟工作站模拟工业场景,结合PC SDK与Win Form技术开发控制端。系统集成了高效的开发工具与接口,简化了构建,提供了用户友好的界面。仿真测试显示其功能完整、操作便捷、系统稳定,支持通过Visual Studio观察与操控机器人生产过程。系统为工业机器人远程监控提供了高效可靠的解决方案,满足了工业生产对自动化、智能化管理的需求。 展开更多
关键词 PC SDK ABB工业机器人 Visual Studio Win Form 远程监控
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Cell communication and relevant signaling pathways in osteogenesis–angiogenesis coupling 被引量:2
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作者 Shuqing Li Xinjia Cai +4 位作者 Jiahe Guo Xiaolu Li Wen Li Yan Liu Mengchun Qi 《Bone Research》 2025年第2期283-306,共24页
Osteogenesis is the process of bone formation mediated by the osteoblasts,participating in various bone-related physiological processes including bone development,bone homeostasis and fracture healing.It exhibits temp... Osteogenesis is the process of bone formation mediated by the osteoblasts,participating in various bone-related physiological processes including bone development,bone homeostasis and fracture healing.It exhibits temporal and spatial interconnectivity with angiogenesis,constructed by multiple forms of cell communication occurring between bone and vascular endothelial cells.Molecular regulation among different cell types is crucial for coordinating osteogenesis and angiogenesis to facilitate bone remodeling,fracture healing,and other bone-related processes.The transmission of signaling molecules and the activation of their corresponding signal pathways are indispensable for various forms of cell communication.This communication acts as a“bridge”in coupling osteogenesis to angiogenesis.This article reviews the modes and processes of cell communication in osteogenesisangiogenesis coupling over the past decade,mainly focusing on interactions among bone-related cells and vascular endothelial cells to provide insights into the mechanism of cell communication of osteogenesis-angiogenesis coupling in different bone-related contexts.Moreover,clinical relevance and applications are also introduced in this review. 展开更多
关键词 fracture healing bone remodeling cell communication ANGIOGENESIS signaling pathways OSTEOGENESIS bone formation forms cell communication
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Geometric size and forming force prediction in incremental flanging:A new analytical model 被引量:1
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作者 Chong TIAN Dawei ZHANG +1 位作者 Guangcan YANG Shengdun ZHAO 《Chinese Journal of Aeronautics》 2025年第2期519-540,共22页
A new analytical model for geometric size and forming force prediction in incremental flanging(IF)is presented in this work.The complex deformation characteristics of IF are considered in the modeling process,which ca... A new analytical model for geometric size and forming force prediction in incremental flanging(IF)is presented in this work.The complex deformation characteristics of IF are considered in the modeling process,which can accurately describe the strain and stress states in IF.Based on strain analysis,the model can predict the material thickness distribution and neck height after IF.By considering contact area,strain characteristics,material thickness changes,and friction,the model can predict specific moments and corresponding values of maximum axial forming force and maximum horizontal forming force during IF.In addition,an IF experiment involving different tool diameters,flanging diameters,and opening hole diameters is conducted.On the basis of the experimental strain paths,the strain characteristics of different deformation zones are studied,and the stable strain ratio is quantitatively described through two dimensionless parameters:relative tool diameter and relative hole diameter.Then,the changing of material thickness and forming force in IF,and the variation of minimum material thickness,neck height,maximum axial forming force,and maximum horizontal forming force with flanging parameters are studied,and the reliability of the analytical model is verified in this process.Finally,the influence of the horizontal forming force on the tool design and the fluctuation of the forming force are explained. 展开更多
关键词 Incremental flanging Analytical model Strain characteristic Geometric size Forming force
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Reservoir Forming Conditions and Models of Oil Sands in Northwestern Margin of Junggar Basin,China 被引量:1
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作者 Xiaoping Ma Xinguo Zhuang +6 位作者 Yunlong He Jibin Zhou Meng Wang Baoqing Li Zhenlong Dai Xudong Fan Haihuai Sun 《Journal of Earth Science》 2025年第2期611-626,共16页
The northwestern margin of Junggar Basin is the region with the richest oil sand resources in China.For better understanding the enrichment rules and deployment of exploration and development of regional oil sand,it i... The northwestern margin of Junggar Basin is the region with the richest oil sand resources in China.For better understanding the enrichment rules and deployment of exploration and development of regional oil sand,it is of great scientific significance to study the accumulation conditions of oil sand in different strata and mining areas of the Junggar Basin.Through a large number of field investigations,drilling verification and sampling tests,it is found that the oil sand in the region covers an area of 2000 km^(2),with shallow and thick reservoir,and predicted resource of 180 million tons.The oil sand resources are mainly distributed in four geological strata,namely the Middle Triassic Karamay Formation,Early Jurassic Badaowan Formation,Late Jurassic Qigu Formation,and Early Cretaceous Qingshuihe Formation.The reservoir is mainly composed of sandstone with high porosity and permeability,and the reservoir space is mainly intergranular pores with a medium average oil content.The oil sand deposit in the region is a typical destructive oil reservoir.The crude oil in the oil sand layer is degraded and thickened from the deep to the shallow,the content of saturated hydrocarbon decreased,and the content of aromatic hydrocarbon,non-hydrocarbon and asphaltene increased.The oil source comes from the deep Permian hydrocarbon-generating depression.Unconformities,faults and marginal fan delta-braided river depositional systems constitute effective migration and storage systems.Caprocks of the Upper Triassic Baijiantan Formation,Lower Jurassic Sangonghe Formation and Lower Cretaceous Hutubihe Formation were formed by three large scale lake transgressions.The Indosinian,Yanshan and Late Yanshan movements are the main driving forces for the migration of deep oil and gas to the shallow edge to form oil sand deposits.It is considered that the oil sand in the northwestern margin of Junggar Basin is of a slope complex migration type. 展开更多
关键词 oil sand reservoir forming conditions accumulation model Junggar Basin petroleum geology
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Additive Manufacturing of Lunar Regolith:A Review 被引量:1
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作者 Wucheng Sun Fen Dang +4 位作者 Yan Zhou Shifeng Wen Cheng Zhou Yusheng Shi Lieyun Ding 《Additive Manufacturing Frontiers》 2025年第3期44-60,共17页
Lunar in-situ construction using additive manufacturing(AM)technology has emerged as a critical pathway for sustainable extraterrestrial exploration.This review systematically evaluates two dominant AM paradigms for l... Lunar in-situ construction using additive manufacturing(AM)technology has emerged as a critical pathway for sustainable extraterrestrial exploration.This review systematically evaluates two dominant AM paradigms for lunar regolith processing:low-temperature deposition forming(material extrusion and binder jetting),and high-energy beam additive manufacturing(powder bed fusion and directed energy deposition).Low-temperature methods achieve moderate compressive strength with low energy consumption but face challenges such as binder dependency and vacuum instability.By contrast,high-energy beam techniques enable binder-free fabrication with better compatibility for in-situ resource utilization,though they suffer from porosity,high energy intensity,and geometric limitations.In the context of lunar in-situ resource utilization(ISRU),low-temperature methods offer near-term feasibility for small-scale infrastructure,while high-energy approaches show promise for large-scale,autonomous construction by leveraging solar energy and raw regolith.Future advancements will hinge on hybrid systems that integrate material efficiency,energy sustainability,and robotic adaptability to overcome extreme environmental challenges.This review consolidates technological progress,identifies interdisciplinary synergies,and provides strategic insights into guiding the transition from Earth-dependent prototypes to self-sufficient lunar habitats,ultimately advancing the capability of humanity for a long-term extraterrestrial presence. 展开更多
关键词 Lunar regolith Additive manufacturing Material forming Extraterrestrial construction In-situ resource utilization
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