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Enhancing the performance of AlGaN deep-ultraviolet laser diodes without an electron blocking layer by using a thin undoped Al_(0.8)Ga_(0.2)N strip layer structure
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作者 SANG Xi-en WANG Fang +1 位作者 LIU Jun-jie LIU Yu-huai 《中国光学(中英文)》 北大核心 2026年第2期421-433,共13页
AlGaN-based deep-ultraviolet(DUV)laser diodes(LDs)face performance challenges due to elec-tron leakage and poor hole injection which is often worsened by polarization effects from conventional elec-tron blocking layer... AlGaN-based deep-ultraviolet(DUV)laser diodes(LDs)face performance challenges due to elec-tron leakage and poor hole injection which is often worsened by polarization effects from conventional elec-tron blocking layers(EBLs).To overcome these limitations,we propose an EBL-free DUV LD design incor-porating a 1-nm undoped Al_(0.8)Ga_(0.2)N thin strip layer after the last quantum barrier.Using PICS3D simula-tions,we evaluate the optical and electrical characteristics.Results show a significant increase in effective electron barrier height(from 158.2 meV to 420.7 meV)and a reduction in hole barrier height(from 149.2 meV to 62.8 meV),which enhance hole injection and reduce electron leakage.The optimized structure(LD3)achieves a 14%increase in output power,improved slope efficiency(1.85 W/A),and lower threshold current.This design also reduces the quantum confined Stark effect and forms dual hole accumulation regions,im-proving recombination efficiency. 展开更多
关键词 ALGAN deep ultraviolet laser diodes undoped thin strip structure without an electron blocking layers
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Point-of-care antigen detection for porcine deltacoronavirus:Colloidal gold and fluorescent immunochromatographic test strips
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作者 Zezhao Cao Junchao Shi +9 位作者 Ruijie Hu Jun Xue Gaili Wang Zi Li Huabo Yu Wei Liu Wenqi He Hualei Wang Haili Zhang Yungang Lan 《Journal of Integrative Agriculture》 2026年第1期394-397,共4页
Highlights By conjugating the same anti-N monoclonal antibody(mAb4-mAb1)with colloidal gold or fluorescent microspheres,this study developed two rapid point-of-care antigen immunochromatographic strips for the detecti... Highlights By conjugating the same anti-N monoclonal antibody(mAb4-mAb1)with colloidal gold or fluorescent microspheres,this study developed two rapid point-of-care antigen immunochromatographic strips for the detection of porcine deltacoronavirus.The fluorescent microsphere-based lateral flow test strip demonstrated a sensitivity of 10^(1.7)TCID_(50)/0.1 mL,which is fourfold higher than that of the colloidal gold-based assay.Porcine deltacoronavirus(PDCoV)is a recently identified enteric coronavirus that causes an acute infectious disease in piglets,leading to diarrhea,vomiting,dehydration,and mortality(Hu et al.2015). 展开更多
关键词 enteric coronavirus point care antigen detection fluorescent microspheresthis immunochromatographic strips porcine deltacoronavirusthe fluorescent immunochromatographic test strips colloidal gold porcine deltacoronavirus
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简谈Buffer区域漫延机制对CBTC列车运行影响
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作者 施宇锋 《铁路通信信号工程技术》 2026年第2期103-108,共6页
基于列车定位与安全防护包络计算原理,重点分析基于通信的列车控制(CBTC)系统中列车安全防护缓冲(Buffer)区域的生成与漫延机制。通过构建不同运营场景,系统研究前车丢失定位或车载ATP故障时,Buffer区域漫延对后续CBTC列车运行的影响规... 基于列车定位与安全防护包络计算原理,重点分析基于通信的列车控制(CBTC)系统中列车安全防护缓冲(Buffer)区域的生成与漫延机制。通过构建不同运营场景,系统研究前车丢失定位或车载ATP故障时,Buffer区域漫延对后续CBTC列车运行的影响规律。结果表明,Buffer区域漫延会导致后车移动授权受限甚至触发紧急制动,进而降低线路通过能力。为此,提出合理增加计轴点布局、优化列车追踪间隔等应对措施,可为实际运营中故障情况下的行车组织与效率提升提供参考。 展开更多
关键词 安全防护包络 CBTC buffer 漫延机制
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Rhizosphere flavonoids alleviate inhibition of soybean nodulation caused by shading under maize–soybean strip intercropping
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作者 Ping Lin Shanshan Liu +9 位作者 Zhidan Fu Kai Luo Yiling Li Xinyue Peng Xiaoting Yuan Lida Yang Tian Pu Yuze Li Taiwen Yong Wenyu Yang 《Journal of Integrative Agriculture》 2026年第3期952-964,共13页
Flavonoids produced by legume roots act as signaling molecules that induce the expression of nod genes in symbiotic rhizobia.However,the role of flavonoids in root exudates under intercropping systems in promoting soy... Flavonoids produced by legume roots act as signaling molecules that induce the expression of nod genes in symbiotic rhizobia.However,the role of flavonoids in root exudates under intercropping systems in promoting soybean nodulation remains unclear.Two consecutive years of field experiments were conducted using maize–soybean strip intercropping with interspecific row spacings of 30 cm(MS30),45 cm(MS45),and 60 cm(MS60),along with sole cropping of soybean(SS)and maize(MM).Root interactions were manipulated using either no root barrier(NB)or a polyethylene plastic barrier(PB)to assess the relationship between flavonoids in root exudates and soybean nodulation.We found that root–root interaction between soybean and maize increased nodule number and fresh weight in intercropped soybean,with enhancement gradually increasing as interspecific distance widened.The proportion of nodules with diameters exceeding 0.4 cm was higher in intercropped soybean under NB compared to PB.Additionally,the expression of nodule-related genes-GmENOD40,Gm NIN2b,and Gm EXPB2-was up-regulated.Furthermore,compared to monocropping,isoflavone secretion by soybean roots decreased,whereas flavonoid and flavonol secretion by both maize and soybean roots increased under intercropping.The abundance of differentially secreted flavonoid metabolites in the rhizosphere of both species declined when root contact was prevented by the barrier.In soybean roots,the expression of Gm CHS8 and Gm IFS1 was up-regulated,while Gm ICHG was down-regulated under root interaction.Most flavonoid and flavonol compounds showed positive correlations with nodule diameter.Nodule number,fresh weight,and the proportion of nodules larger than 0.2 cm increased in diverse soybean genotypes treated with maize root exudates,which contributed to enhanced nitrogen fixation capacity.Therefore,maize–soybean strip intercropping,combined with optimal row spacing,enhances the positive effects of underground root interactions and improves nodulation and nitrogen fixation in intercropped soybean. 展开更多
关键词 maize–soybean strip intercropping root interaction FLAVONOIDS NODULE
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Evolution of microstructure and properties of Cu-12Fe alloys prepared by twin-roll strip casting
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作者 Tian-mo Wu Yuan-xiang Zhang +3 位作者 Shuai-jie Guo Nuo-jin Wang Jian Kang Guo Yuan 《China Foundry》 2026年第1期73-82,共10页
The Cu-12Fe alloy has attracted significant attention due to its excellent electrical conductivity and electromagnetic shielding capability,high strength,cost-effectiveness,and recyclability.In the present work,the Cu... The Cu-12Fe alloy has attracted significant attention due to its excellent electrical conductivity and electromagnetic shielding capability,high strength,cost-effectiveness,and recyclability.In the present work,the Cu-12Fe alloy strip with the thickness of 2.4 mm was successfully produced by twin-roll strip casting.The microstructure and properties of the Cu-12Fe alloy were tailored by cold rolling and aging treatment.The tensile strength of the as-cast strip is approximately 328 MPa and its elongation is 25%.The Fe phase randomly dispersed in the matrix,and the average size of Fe-rich phase is 2μm.Besides,enrichment of Fe phase is observed in the central layer of the strip,results in the formation of the“sandwich structure”.Moreover,the as-cast strip of Cu-12Fe was directly cold-rolled from 2.4 to 0.12 mm.The directly cold-rolled sample after aging at 450℃for 16 h(ProcessⅠ)shows excellent electrical conductivity of 69.5%IACS,the tensile strength and elongation are 513 MPa and 3.8%,the saturation magnetic flux density is 20.1 emu·g^(-1),and the coercive force is 25.2 Oe.In ProcessⅡ,the as-cast strip firstly cold-rolled to 1.2 mm,then aged at 500℃for 1.5 h,followed by cold rolling to 0.12 mm,finally aged at 450℃for 16 h.The sample after ProcessⅡshows the electrical conductivity of 66.3%IACS,the tensile strength of 533 MPa,an elongation of 3.5%,saturation magnetic flux density of 21.4 emu·g^(-1),and the coercive force of 22.3 Oe. 展开更多
关键词 Cu-Fe alloy twin-roll strip casting MICROSTRUCTURE mechanical properties thermal aging electrical conductivity
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Erosion-immune Layer-by-layer Deposition Enabled by Interfacial Buffering toward 20.21%-Efficient Pseudo-Planar Heterojunction Organic Solar Cells
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作者 Dan Liu Jin-Yang Yu +9 位作者 Yu-Ang Fu Ming-Tao Liu Pei-Pei Zhu Jia-Nan Fang Xin Song Hai-Ming Zhu Xin-Hui Lu Hong-Zheng Chen Xun-Fan Liao Yi-Wang Chen 《Chinese Journal of Polymer Science》 2026年第4期922-936,I0008,共16页
The pseudo-planar heterojunction(PPHJ)structure obtained via layer-by-layer(LBL)deposition offers a promising pathway for efficient and stable organic solar cells(OSCs);however,solvent-induced swelling and erosion of ... The pseudo-planar heterojunction(PPHJ)structure obtained via layer-by-layer(LBL)deposition offers a promising pathway for efficient and stable organic solar cells(OSCs);however,solvent-induced swelling and erosion of the donor layer during acceptor deposition often hinder the formation of an ideal vertical phase separation(VPS)morphology.Here,a simple approach for incorporating a highly crystalline polymer as a buffer layer between the donor and acceptor layers is proposed.We investigated the effectiveness of this strategy by constructing three systems:PM6/L8-BO,PM6:D18/L8-BO,and PM6/D18/L8-BO.Compared with the other two systems,when deposited as a separate layer,D18 with low surface energy forms a dense crystalline fibrillar network,effectively suppressing L8-BO over-penetration and mitigating chloroform-induced PM6 erosion.This architecture achieves the most favorable VPS morphology with an improved donor/acceptor gradient distribution and higher phase purity,facilitating charge transport and suppressing recombination.Moreover,the D18 buffer layer can regulate molecular packing,improve active layer crystallinity,and passivate interfacial defects to reduce energy loss.Consequently,the PM6/D18/L8-BO-based device achieved a superior power conversion efficiency(PCE)of 19.80%.Notably,integrating BTP-e C9 further increased the PCE to 20.21%.This study demonstrates that introducing a highly crystalline polymer as a p-i-n buffer layer can effectively optimize the VPS morphology,enabling highperformance PPHJ OSCs. 展开更多
关键词 Organic solar cells Pseudo-planar heterojunctions buffer layer Highly crystalline Vertical phase separation
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Predictive modeling for mechanical properties of cold-rolled strip steel based on random forest regression and whale optimization algorithm
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作者 Hong-Lei Cai Yi-Ming Fang +3 位作者 Le Liu Li-Hui Ren Zhen-Dong Liu Xiao-Dong Zhao 《Journal of Iron and Steel Research International》 2026年第3期73-87,共15页
In response to the challenges of inadequate predictive accuracy and limited generalization capability in data-driven modeling for the mechanical properties of the cold-rolled strip steel,a predictive modeling method n... In response to the challenges of inadequate predictive accuracy and limited generalization capability in data-driven modeling for the mechanical properties of the cold-rolled strip steel,a predictive modeling method named RFR-WOA is developed based on random forest regression(RFR)and whale optimization algorithm(WOA).Firstly,using Pearson and Spearman correlation analysis and Gini coefficient importance ranking on an actual production dataset containing 37,878 samples,22 key variables are selected as model inputs from 112 variables that affect mechanical properties.Subsequently,an RFR-based predictive model for the mechanical properties of cold-rolled strip steel is constructed.Then,with the combination of the coefficient of determination(R^(2))and root mean square error as the optimization objective,the hyperparameters of RFR model are iteratively optimized using WOA,and better predictive effectiveness is obtained.Finally,the mechanical properties prediction model based on RFR-WOA is compared with models established using deep neural networks,convolutional neural networks,and other methods.The test results on 9469 samples of actual production data show that the model developed present has better predictive accuracy and generalization capability. 展开更多
关键词 Cold-rolled strip steel Mechanical property Predictive modeling Random forest regression Whale optimization algorithm
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Combined liver resection and peritoneal stripping for Echinococcus multilocularis
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作者 Kaitlyn R Musto Kristopher P Croome 《Hepatobiliary & Pancreatic Diseases International》 2026年第1期97-99,共3页
Echinococcus is a zoonotic parasite and 1 of 17 neglected tropical diseases with a worldwide distribution.The World Health Organization(WHO)targeted for control or elimination by 2050[1,2].Two main species of Echinoco... Echinococcus is a zoonotic parasite and 1 of 17 neglected tropical diseases with a worldwide distribution.The World Health Organization(WHO)targeted for control or elimination by 2050[1,2].Two main species of Echinococcus infect humans:Echinococcus granulosus,causing cystic echinococcosis(CE),and Echinococcus multilocularis(EM),causing alveolar echinococcosis(AE)[3].AE is much rarer but far more severe than CE and ranks as one of the most dangerous helminthic zoonoses in the world[4,5].Humans are rare aberrant intermediate hosts and typically become infected through the ingestion of EM eggs shed in the feces of definitive hosts[6].After an incubation period of many years,humans may develop AE[7].While slow-growing,AE is a devastating clinical condition characterized by silent progression and infiltrative proliferation of the parasite,mimicking a malignancy[7].Without appropriate treatment,AE has a death rate of more than 90%within 10 years of diagnosis[5].For this reason,AE must be considered in the differential diagnosis of patients presenting with a hepatic mass or malignancy. 展开更多
关键词 Echinococcus multilocularis echinococcus multilocularis em causing neglected tropical diseases Liver resection cystic echinococcosis ce helminthic zoonoses alveolar echinococcosis ae ae Peritoneal stripping
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Aluminum foam as buffer layer used in soft rock tunnel with large deformation 被引量:2
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作者 WU Faquan MIAO Binxin +2 位作者 TIAN Yun ZHANG Fang ZHANG Chaoxuan 《Journal of Mountain Science》 2025年第1期324-336,共13页
The squeezing deformation of surrounding rock is an important factor restricting the safe construction and long-term operation of tunnels when a tunnel passes through soft strata with high ground stress.Under such sof... The squeezing deformation of surrounding rock is an important factor restricting the safe construction and long-term operation of tunnels when a tunnel passes through soft strata with high ground stress.Under such soft rock geological conditions,the large deformation of the surrounding rock can easily lead to the failure of supporting structures,including shotcrete cracks,spalling,and steel arch distortion.To improve the lining support performance during the large deformation of squeezed surrounding rock,this work selects aluminum foam with densities of 0.25 g/cm3,0.42 g/cm3 and 0.61 g/cm3 as the buffer layer material and carries out uniaxial confined compression tests.Through the evaluation and analysis of energy absorption and the comparison of the yield pressure of aluminum foam with those of other cushioning materials and yield pressure support systems,the strength,deformation and energy absorption of aluminum foam with a density of 0.25 g/cm3 meet the yield pressure performance requirements.The numerical model of the buffer layer yielding support system is then established via the finite element analysis software ABAQUS,and the influence of the buffer layer setting on the lining support is analyzed.Compared with the conventional support scheme,the addition of an aluminum foam buffer layer can reduce the stress and deformation of the primary support and secondary lining.The maximum and minimum principal stresses of the primary support are reduced by 13%and 15%,respectively.The maximum and minimum principal stresses of the secondary lining are reduced by 15%and 12%,respectively,and the displacement deformation of the secondary lining position is reduced by 15%.In summary,the application of aluminum foam buffer layer can reduce the stress and deformation of the primary support and secondary lining,improve the stress safety of the support and reduce the deformation of the support. 展开更多
关键词 Soft rock tunnel Uniaxial confined compression Aluminum foam buffer layer Yielding support
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An optimization framework for hot-rolled strip crown control based on model-driven digital twin 被引量:1
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作者 Fen-jia Wang Chao Liu +6 位作者 An-rui He Yong Song Jian Shao Chi-huan Yao Yi Qiang Hong-yan Liu Bo Ma 《Journal of Iron and Steel Research International》 2025年第7期1920-1939,共20页
Accurate crown control is paramount for ensuring the quality of hot-rolled strip products.Given the multitude of influencing parameters and the intricate coupling and genetic relationships among them,the conventional ... Accurate crown control is paramount for ensuring the quality of hot-rolled strip products.Given the multitude of influencing parameters and the intricate coupling and genetic relationships among them,the conventional crown control method is no longer sufficient to meet the precision requirements of schedule-free rolling.To address this limitation,an optimization framework for hot-rolled strip crown control was developed based on model-driven digital twin(MDDT).This framework enhances the strip crown control precision by facilitating collaborative operations among physical entities,virtual models,and functional application layers.In virtual modeling,a data-driven approach that integrates the extreme gradient boosting and the improved Harris hawk optimization algorithm was firstly proposed to fit the relationship between key process parameters and strip crown,and a global-local collaborative training strategy was proposed to enhance the model adaptability to diverse working conditions.Subsequently,the influence of crucial process factors on the virtual model was examined through model responses.Furthermore,a novel optimization mode for crown control based on MDDT was established by aligning and reconstructing both the physical and virtual models,thereby enhancing the crown control precision.Finally,data trials were conducted to validate the effectiveness of the proposed framework.The results indicated that the proposed method exhibited satisfactory performance and could be effectively utilized to improve the crown control precision. 展开更多
关键词 Hot-rolled strip Crown control Machine learning Digital twin Extreme gradient boosting
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Size Effect of Flow Stress in CoCrNi Medium Entropy Alloy Ultrathin Strips
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作者 Zhi Hui Hou Jinxiong +3 位作者 Ma Shengguo Wang Tao Wang Zhihua Huang Qingxue 《稀有金属材料与工程》 北大核心 2025年第10期2494-2500,共7页
A constitutive model considering the size effect was established to investigate the behavior of CoCrNi medium entropy alloy ultrathin strip in different deformation stages during the uniaxial quasi-static tensile test... A constitutive model considering the size effect was established to investigate the behavior of CoCrNi medium entropy alloy ultrathin strip in different deformation stages during the uniaxial quasi-static tensile test.Results show that when the t/d value is lower than 10.62,the CoCrNi alloy ultrathin strip shows an obvious size-dependent property in the elastic deformation stage.With the decrease in t/d value,the volume fraction of the surface layer grains is increased,leading to the linear decrease in flow stress.In the plastic deformation stage,the material stiffness is correlated with the t/d value.Specifically,as the t/d value increases,the work-hardening capacity of the material is enhanced.When the t/d value increases to 10,the work-hardening capacity reaches a maximum state;when the t/d value is beyond 10,the work-hardening capacity weakens. 展开更多
关键词 medium-entropy alloy ultrathin strip size effect flow stress plastic stiffness
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Study and Application of Soybean and Corn Strip Compound Planting Technology
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作者 Huajun SUN Yue CHEN 《Agricultural Biotechnology》 2025年第4期27-30,共4页
The soybean and corn strip compound planting technology is a crucial measure for improving land use efficiency and ensuring food security.This paper deeply analyzed the principles,advantages,and key technical aspects ... The soybean and corn strip compound planting technology is a crucial measure for improving land use efficiency and ensuring food security.This paper deeply analyzed the principles,advantages,and key technical aspects of this technology,including variety selection,planting pattern,sowing management,and field management.It also illustrated its application effectiveness through practical cases and proposed corresponding solutions to existing challenges in its promotion.This study provides theoretical support and practical reference for the widespread adoption and efficient application of this technology. 展开更多
关键词 SOYBEAN CORN strip compound planting TECHNOLOGY
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Application Effects of Various Herbicides and Essential Techniques in Corn and Soybean Strip Intercropping Fields
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作者 Shandong LI Min WANG +2 位作者 Shaoguo ZHANG Yaling ZHAO Tingting YANG 《Plant Diseases and Pests》 2025年第2期19-23,共5页
[Objectives]To address the weeding challenges within the corn and soybean strip intercropping field and identify appropriate herbicide types and application methods suitable for the corn and soybean strip intercroppin... [Objectives]To address the weeding challenges within the corn and soybean strip intercropping field and identify appropriate herbicide types and application methods suitable for the corn and soybean strip intercropping fields in Siyang County.[Methods]The trial comprised six herbicide treatments and one blank control,with investigations conducted to assess efficacy,safety,and yield.[Results]Each herbicide treatment effectively controlled weeds,demonstrated high safety,and enhanced the yields of both soybeans and corn.The combined application of soil sealing with stem and leaf spray exhibited superior overall weed control compared to soil sealing alone.At 28 d following stem and leaf spray,the plant control effect and fresh weight control effect against weeds in the combined treatment of soil sealing with stem and leaf spray all exceeded 89%.[Conclusions]This study offers technical support for advancing the practice of strip intercropping between corn and soybeans. 展开更多
关键词 CORN SOYBEAN strip INTERCROPPING Control effect HERBICIDE Demonstration test
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Microstructure of interfacial diffusion layer of cross-layered silver-copper composite strip and its effect on resistivity
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作者 Jie Liu Ya-fang Cheng +5 位作者 Pei-yan Li Jiang-tao Hou Fu-li Liu Jian Qin Qing-le Hao Su-juan Zhong 《Journal of Iron and Steel Research International》 2025年第7期1940-1947,共8页
The interfacial structure and its effect on the resistivity of cross-layered silver-copper composite strip fabricated by hot-roll bonding and diffusion welding processes with the same specification were studied.Throug... The interfacial structure and its effect on the resistivity of cross-layered silver-copper composite strip fabricated by hot-roll bonding and diffusion welding processes with the same specification were studied.Through optical and scanning electron microscope analysis of metallographic structure of the diffusion region of interface,it is found that the thickness of the interfacial diffusion layer is related to the composite conditions.Under the condition of sufficient diffusion,the interface of silver-copper composite strip produced by diffusion welding process has a wider interfacial transition region and fine grain area.Due to the higher diffusion rate of copper atoms than that of silver atoms,copper atoms tend to aggregate at the silver boundaries to form a copper-rich second solid solution,which has a fixing and expanding effect during annealing.The fine grain area at the interface of the composite strip produced by diffusion welding process still exists after annealing treatment and reaches a width of 55-97μm.While the fine grain region at the interface of hot-rolled composite strips is mainly formed by crushing the surface under rolling pressure with less diffusion effect,it almost disappears after annealing.The resistivity of silver-copper composite strip increases with the extension of the interfacial diffusion region.The resistivity of hot-roll bonding composite strip is increased by about 4%higher than that of the theoretical calculation,while the resistivity of diffusion welding composite strip is increased by 6%. 展开更多
关键词 Silver-copper composite strip Roll bonding Diffusion welding Resistivity-Interface
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Effects of the buffer layer on the Casimir pressure of peptide films deposited on a substrate
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作者 Dingding Lv Shuai Zhou +2 位作者 Kaipeng Liu Shiwei Dai Lixin Ge 《Chinese Physics B》 2025年第10期385-390,共6页
The Casimir pressure plays an important role in the adhesion stability of nanofilms at submicro scales.In this work,the Casimir pressure of peptide films deposited on a layered substrate is investigated.Three types of... The Casimir pressure plays an important role in the adhesion stability of nanofilms at submicro scales.In this work,the Casimir pressure of peptide films deposited on a layered substrate is investigated.Three types of semi-infinite substrates,i.e.,silica,silicon and gold,are considered.The buffer layer between the peptide film and substrate consists of silicon or silica.The switching sign of the Casimir pressure can be controlled in a region ranging from about 130 nm to 1000 nm,depending on the thickness of the buffer layer and the substrate.The results suggest that the critical thickness of peptide films for Casimir equilibrium increases(or decreases)by increasing the thickness of the silicon(or silica)buffer film.The influences of wetting and electrolyte screening on the Casimir pressure are also investigated.Our finding provides a theoretical guide for the adhesion stability of peptide films in organic electronics. 展开更多
关键词 Casimir pressure buffer layer peptide films electrolyte screening
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Experimental determination of stripping foil thickness on the XiPAF synchrotron
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作者 Xiao-Yu Liu Hong-Juan Yao +4 位作者 Shu-Xin Zheng Ze-Jiang Wang Yang Xiong Pei-Zhi Fang Zhong-Ming Wang 《Nuclear Science and Techniques》 2025年第3期27-37,共11页
Stripping injection overcomes the limitations of Liouville's theorem and is widely used for beam injection and accumulation in high-intensity synchrotrons.The interaction between the stripping foil and beam is cru... Stripping injection overcomes the limitations of Liouville's theorem and is widely used for beam injection and accumulation in high-intensity synchrotrons.The interaction between the stripping foil and beam is crucial in the study of stripping injection,particularly in low-energy stripping injection synchrotrons,such as the XiPAF synchrotron.The foil thickness is the main parameter that affects the properties of the beam after injection.The thin stripping foil is reinforced with collodion during its installation.However,the collodion on the foil surface makes it difficult to determine its equivalent thickness,because the mechanical measurements are not sufficiently reliable or convenient for continuously determining foil thickness.We propose an online stripping foil thickness measurement method based on the ionization energy loss effect,which is suitable for any foil thickness and does not require additional equipment.Experimental studies were conducted using the XiPAF synchrotron.The limitation of this method was examined,and the results were verified by comparing the experimentally obtained beam current accumulation curves with the simulation results.This confirms the accuracy and reliability of the proposed method for measuring the stripping foil thickness. 展开更多
关键词 stripping injection Foil thickness SYNCHROTRON Injection efficiency Experimental study
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Review of imaging buffers used in stochastic optical reconstruction microscopy
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作者 Can Wang Zhe Sun Donghan Ma 《Chinese Chemical Letters》 2025年第9期56-63,共8页
Stochastic optical reconstruction microscopy(STORM),as a typical technique of single-molecule localization microscopy(SMLM),has overcome the diffraction limit by randomly switching fluorophores between fluorescent and... Stochastic optical reconstruction microscopy(STORM),as a typical technique of single-molecule localization microscopy(SMLM),has overcome the diffraction limit by randomly switching fluorophores between fluorescent and dark states,allowing for the precise localization of isolated emission patterns and the super-resolution reconstruction from millions of localized positions of single fluorophores.A critical factor influencing localization precision is the photo-switching behavior of fluorophores,which is affected by the imaging buffer.The imaging buffer typically comprises oxygen scavengers,photo-switching reagents,and refractive index regulators.Oxygen scavengers help prevent photobleaching,photo-switching reagents assist in facilitating the conversion of fluorophores,and refractive index regulators are used to adjust the refractive index of the solution.The synergistic interaction of these components promotes stable blinking of fluorophores,reduces irreversible photobleaching,and thereby ensures high-quality super-resolution imaging.This review provides a comprehensive overview of the essential compositions and functionalities of imaging buffers used in STORM,serving as a valuable resource for researchers seeking to select appropriate imaging buffers for their experiments. 展开更多
关键词 Single-molecule localization microscopy Stochastic optical reconstruction microscopy Photo-switching Photobleaching Imaging buffer
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Vacuum ammonia stripping from liquid digestate:Effects of pH,alkalinity,temperature,negative pressure and process optimization
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作者 Qiuhong Chen Donghai Yang +3 位作者 Xiang Chen Xiankai Wang Bin Dong Xiaohu Dai 《Journal of Environmental Sciences》 2025年第3期638-650,共13页
High ammonia-nitrogen digestate has become a key bottleneck limiting the anaerobic digestion of organic solid waste.Vacuum ammonia stripping can simultaneously remove and recover ammonia nitrogen,which has attracted a... High ammonia-nitrogen digestate has become a key bottleneck limiting the anaerobic digestion of organic solid waste.Vacuum ammonia stripping can simultaneously remove and recover ammonia nitrogen,which has attracted a lot of attention in recent years.To investigate the parameter effects on the efficiency and mass transfer,five combination conditions(53℃ 15 kPa,60°C 20 kPa,65°C 25 kPa,72°C 35 kPa,and 81°C 50 kPa)were conducted for ammonia stripping of sludge digestate.The results showed that 80%of ammonia nitrogen was stripped in 45 min for all experimental groups,but the ammonia transfer coefficient varied under different conditions,which increased with the rising of boiling point temperature,and reached the maximum value(39.0 mm/hr)at 81°C 50 kPa.The ammonia nitrogen removal efficiency was more than 80%for 30 min vacuum stripping after adjusting the initial pH to above 9.5,and adjustment of the initial alkalinity also affects the pH value of liquid digestate.It was found that pH and alkalinity are the key factors influencing the ammonia nitrogen dissociation and removal efficiency,while temperature and vacuum mainly affect the ammonia nitrogen mass transfer and removal velocity.In terms of the mechanism of vacuum ammonia stripping,it underwent alkalinity destruction,pH enhancement,ammonia nitrogen dissociation,and free ammonia removal.In this study,two-stage experiments of alkalinity destruction and ammonia removal were also carried out,which showed that the two-stage configuration was beneficial for ammonia removal.It provides a theoretical basis and practical technology for the vacuum ammonia stripping from liquid digestate of organic solid waste. 展开更多
关键词 Liquid digestate Vacuum ammonia stripping ALKALINITY Mass transfer Process optimization
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A moving model test of a maglev train passing through tunnels:Effect of train speed and buffer structure on aerodynamic environment
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作者 GUO Zi-jian CHEN Zheng-wei +2 位作者 GUO Zhan-hao ZENG Guang-zhi PENG Cheng 《Journal of Central South University》 2025年第12期4868-4884,共17页
Maglev trains experience significant aerodynamic effects when passing through tunnels.A moving model test was conducted to explore the practical effects of speed reduction and entrance buffer structures on mitigating ... Maglev trains experience significant aerodynamic effects when passing through tunnels.A moving model test was conducted to explore the practical effects of speed reduction and entrance buffer structures on mitigating tunnel/maglev aerodynamic effects.It is found that both have an overall positive effect on mitigating the aerodynamic environment inside and outside the tunnel.Trains operating at 200 km/h show a 49.8%decrease in peak-to-peak pressure and a 50.7%decrease in transient pressure instability on inner walls compared to those at 280 km/h.Lower speeds resulted in a 65.6%decrease in amplitude and a 24.5%decrease in decay rate,both of which are parameters for exponential fittings of pressure peaks that decay naturally after the train leaves.The buffer structures result in a reduction of up to 25.7%in the maximum positive pressure and a 29.0%decrease in transient pressure instability.Additionally,a reduction in amplitude of up to 21.2%and a 32.2%increase in decay rate were observed with the use of buffer structures.Nevertheless,it is difficult to conclude direct correlations between the maximum pressure,peak-to-peak values,etc.,and the speeds or buffer structures due to the complex wave propagation in tunnels.However,speed reduction and buffer structures are proven to be effective in reducing the micro-pressure wave levels with a simpler monotonic relationship. 展开更多
关键词 maglev train TUNNEL moving model test buffer structure micro-pressure wave
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Impacts of Various Herbicide Concentrations on Weed Control Effect and Crop Yield in Soybean and Corn Strip Intercropping Systems
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作者 Lixian RAO Hongyan DI +5 位作者 Jiawei ZUO Xue WANG Yashu QI Ping YONG Biao ZHU Guoying YANG 《Plant Diseases and Pests》 2025年第5期17-19,22,共4页
[Objectives]To identify the optimal combination of herbicide concentrations appropriate for soil closed weeding in the soybean and corn intercropping system in Zhongwei City.[Methods]Two herbicides,96%(S)-metolachlor ... [Objectives]To identify the optimal combination of herbicide concentrations appropriate for soil closed weeding in the soybean and corn intercropping system in Zhongwei City.[Methods]Two herbicides,96%(S)-metolachlor and 75%thifensulfuron methyl,were selected for this experiment.A no-herbicide treatment served as the control,and five concentration gradients of the herbicides were established.Prior to sowing,the soil underwent a closed weeding treatment.The impacts of various herbicide concentration combinations on growth indicators,weed control effect,and the yields of soybean and corn across various treatments were analyzed.[Results]The tested combinations of herbicide concentrations did not result in significant phytotoxicity to soybean and corn seedlings.Furthermore,as the herbicide concentrations increased in each treatment,treatments D and E demonstrated the most effective weed control effect.Specifically,40 d post application,the plant control effect and fresh weight control effect reached 97.25% and 98.03% for treatment D,and 97.25% and 98.24% for treatment E,respectively.Additionally,the yields of both soybean and corn showed significant increases.[Conclusions]Considering the overall output-input ratio in this region,treatment D,comprising 96%(S)-metolachlor at 1650 mL/hm^(2) and 75% thifensulfuron-methyl at 48 g/hm^(2),can be identified as the herbicide concentration combination that provides the most effective weed control effect in the soybean and corn strip intercropping system. 展开更多
关键词 Soybean and corn strip intercropping Closed weeding Control effect Yield
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