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基于数据驱动的乙二醇精馏过程能耗与产品质量建模
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作者 冯康康 耿欣 +4 位作者 娄清辉 王玉 胡华军 石祥建 薄翠梅 《过程工程学报》 北大核心 2025年第2期142-149,共8页
能耗和产品质量是精馏过程中的重要经济指标,能耗和产品质量预测是实现工艺优化操作的必要环节。以煤制乙二醇精馏过程为例,采用一种改进的最小二乘支持向量机算法,构建乙二醇精馏过程能耗与产品质量模型。首先基于煤制乙二醇精馏过程... 能耗和产品质量是精馏过程中的重要经济指标,能耗和产品质量预测是实现工艺优化操作的必要环节。以煤制乙二醇精馏过程为例,采用一种改进的最小二乘支持向量机算法,构建乙二醇精馏过程能耗与产品质量模型。首先基于煤制乙二醇精馏过程的工业数据,采用互信息法提取关键特征参数,进行变量筛选和数据预处理。然后引入局部目标集提高模型预测精度,并通过UMDA算法进行迭代寻优,得到LSSVM模型的最佳超参数。最后采用改进的LSSVM算法对数据样本建模,验证了算法的有效性。后续可以将模型作为多目标优化问题的目标函数求解最佳操作参数,来达到稳定操作、提高产品质量、避免过度分离操作以及降低精馏过程能耗的目的。 展开更多
关键词 煤制乙二醇 数据驱动建模 最小二乘支持向量机 能耗 质量
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纳米酶 被引量:25
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作者 范克龙 高利增 +39 位作者 魏辉 江冰 王大吉 张若飞 贺久洋 孟祥芹 王卓然 樊慧真 温涛 段德民 陈雷 姜伟 芦宇 蒋冰 魏咏华 李唯 袁野 董海姣 张鹭 洪超仪 张紫霞 程苗苗 耿欣 侯桐阳 侯亚欣 李建茹 汤国恒 赵越 赵菡卿 张帅 谢佳颖 周子君 任劲松 黄兴禄 高兴发 梁敏敏 张宇 许海燕 曲晓刚 阎锡蕴 《化学进展》 SCIE CAS CSCD 北大核心 2023年第1期1-87,共87页
纳米酶(Nanozymes)是由我国科学家首次提出的新概念,它是一类具有生物催化功能的纳米材料,能够基于特定的纳米结构催化天然酶的底物并作为酶的代替品。自2007年首次报道以来,全球已有来自于55个国家的420多个研究机构证实了纳米酶的普... 纳米酶(Nanozymes)是由我国科学家首次提出的新概念,它是一类具有生物催化功能的纳米材料,能够基于特定的纳米结构催化天然酶的底物并作为酶的代替品。自2007年首次报道以来,全球已有来自于55个国家的420多个研究机构证实了纳米酶的普遍规律。纳米酶的发现第一次揭示纳米材料蕴含一种独特的纳米效应———类酶催化效应。纳米酶作为一种新材料,既有纳米材料本身的理化性质,又有类似酶的催化功能,兼具天然酶与人工酶的优势于一身。其中,纳米结构不仅赋予纳米酶高效催化功能,而且使纳米酶比天然酶稳定,易于规模化生产。另外,纳米酶独特的多酶活性将为设计廉价、稳定、各种各样全新的催化级联反应提供功能分子。纳米酶是多学科交叉融合的典范,2022年被IUPAC评为十大化学新兴技术。在全球从事化学、酶学、材料学、生物学、医学、理论计算等多领域科学家的共同推进下,如今纳米酶已经成为新的研究热点。我国科学家在这一新兴领域一直发挥着引领作用,解析了纳米酶的构⁃效关系,将其催化活性提高了约1万倍,实现了超越天然酶的理性设计,创造了全球首个纳米酶产品,出版了纳米酶学英文专著,发布纳米酶术语及中国/国际标准化。更可喜的是,纳米酶新领域汇集了一大批多学科交叉融合的优秀青年科学家,推动纳米酶进入高速发展阶段,纳米酶的种类已经超过1200多种,其催化机制研究也更加深入,应用研究也从当初的检测逐步拓展到纳米酶催化医学、传感检测、绿色合成、新能源、环境治理等多个领域。本文向读者介绍纳米酶自发现以来的主要进展,包括最近发现的天然纳米酶,期待纳米酶从新概念、新材料衍生出新技术、新产品、新商品,服务人类健康,并带动新学科发展。 展开更多
关键词 纳米酶 酶催化 生物催化 多酶活性
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Volumetric Stress Managements on Silicon Anode of Lithium-Ion Batteries by a Self-Adaptable Binder
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作者 Shuai Wu Lanying He +8 位作者 Yue Lu Jingang Zheng Lixiang Li xin geng Chengguo Sun Hongwei Zhao Guangshen Jiang Fang Di Baigang An 《Energy & Environmental Materials》 2025年第3期58-67,共10页
The intrinsic volume changes(about 300%)of Si anode during the lithiation/delithiation leads to the serious degradation of battery performance despite of theoretical capacity of 3579 mAh g^(-1) of Si.Herein,a three-di... The intrinsic volume changes(about 300%)of Si anode during the lithiation/delithiation leads to the serious degradation of battery performance despite of theoretical capacity of 3579 mAh g^(-1) of Si.Herein,a three-dimensional(3D)conductive polymer binder with adjustable crosslinking density has been designed by employing citric acid(CA)as a crosslinker between the carboxymethyl cellulose(CMC)and the poly(3,4-ethylenedioxythiophene)poly-(styrene-4-sulfonate)(PEDOT:PSS)to stabilize Si anode.By adjusting the crosslinking density,the binder can achieve a balance between rigidity and flexibility to adapt the volume expansion upon lithiation and reversible volume recovery after delithiation of Si.Therefore,Si/CMC-CA-PEDOT:PSS(Si/CCP)electrode demonstrates an excellent performance with high capacities of 2792.3 mAh g^(-1) at 0.5 A g^(-1) and a high area capacity above 2.6 mAh cm^(-2) under Si loading of 1.38 mg cm^(-2).The full cell Si/CCP paired with Li(Ni_(0.8)Co_(0.1)Mn_(0.1))O_(2) cathode discharges a capacity of 199.0 mAh g^(-1) with 84.3%ICE at 0.1 C and the capacity retention of 95.6%after 100 cycles.This work validates the effectiveness of 3D polymer binder and provides new insights to boost the performance of Si anode. 展开更多
关键词 3D conductive polymer binder crosslinking density self-adapting silicon anode
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Electroacupuncture in the repair of spinal cord injury:inhibiting the Notch signaling pathway and promoting neural stem cell proliferation 被引量:34
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作者 xin geng Tao Sun +3 位作者 Jing-hui Li Ning Zhao Yong Wang Hua-lin Yu 《Neural Regeneration Research》 SCIE CAS CSCD 2015年第3期394-403,共10页
Electroacupuncture for the treatment of spinal cord iniury has a good dinical curative effect, but the underlying mechanism is unclear. In our experiments, the spinal cord of adult Sprague-Daw- ley rats was clamped fo... Electroacupuncture for the treatment of spinal cord iniury has a good dinical curative effect, but the underlying mechanism is unclear. In our experiments, the spinal cord of adult Sprague-Daw- ley rats was clamped for 60 seconds. Dazhui (GV14) and Mingmen (GV4) acupoints of rats were subjected to electroacupuncture. Enzyme-linked immunosorbent assay revealed that the expres- sion of serum inflammatory factors was apparently downregulated in rat models of spinal cord injury after electroacupuncture. Hematoxylin-eosin staining and immunohistochemistry results demonstrated that electroacupuncture contributed to the proliferation of neural stem cells in rat injured spinal cord, and suppressed their differentiation into astrocytes. Real-time quantitative PCR and western blot assays showed that electroacupuncture inhibited activation of the Notch signaling pathway induced by spinal cord injury. These findings indicate that electroacupuncture repaired the injured spinal cord by suppressing the Notch signaling pathway and promoting the proliferation of endogenous neural stem ceils. 展开更多
关键词 nerve regeneration spinal cord electroacupuncture therapy neural stem cells notchsignaling pathway ASTROCYTES inflammation survival curve PROLIFERATION differentiation real-timequantitative PCR western blot assay neural regeneration
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Comprehensive model for a slag bath in electroslag remelting process with a current-conductive mould 被引量:6
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作者 Fu-bin Liu Xi-min Zang +2 位作者 Zhou-hua Jiang xin geng Man Yao 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2012年第4期303-311,共9页
A mathematical model was developed to describe the interaction of multiple physical fields in a slag bath during electroslag remelting (ESR) process with a current-conductive mould. The distributions of current dens... A mathematical model was developed to describe the interaction of multiple physical fields in a slag bath during electroslag remelting (ESR) process with a current-conductive mould. The distributions of current density, magnetic induction intensity, electromagnetic force, Joule heating, fluid flow and temperature were simulated. The model was verified by temperature measurements during remelting 12CrMoVG steel with a slag of 50wt%-70wt% CaF2, 20wt%-30wt% CaO, 10wt%-20wt% A1203, and 〈10wt% SiO2 in a 600 mm diameter current-conductive mould. There is a good agreement between the calculated temperature results and the measured data in the slag bath. The calculated results show that the maximum values of current density, electromagnetic force and Joule heating are in the region between the comer electrodes and the conductivity element. The characteristics of current density distribution, magnetic induction intensity, electromagnetic force, Joule heating, velocity patterns and temperature profiles in the slag bath during ESR process with current-conductive mould were analyzed. 展开更多
关键词 electroslag remelting mathematical models slag bath temperature distribution
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Effect of slag composition on elements oxidation behavior of GH984G superalloy for electroslag remelting withdrawal process 被引量:3
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作者 Fu-bin Liu Jun-zhe Gao +6 位作者 Hai-bo Cao Hua-bing Li Zhou-hua Jiang xin geng Cong-peng Kang Kui Chen Rui-dong An 《Journal of Iron and Steel Research International》 SCIE EI CSCD 2022年第5期761-771,共11页
The composition of a slag system has been shown to be particularly important and influential for the new technology of electroslag remelting withdrawal process.The oxidation of the GH984G alloy elements,in contact wit... The composition of a slag system has been shown to be particularly important and influential for the new technology of electroslag remelting withdrawal process.The oxidation of the GH984G alloy elements,in contact with different contents of CaF_(2)–CaO–Al_(2)O_(3)–MgO–TiO_(2)–SiO_(2)in various slag systems,has been investigated in the present study by performing slag–metal equilibrium experiments and ion and molecule coexistence theory analysis.The results show that CaF_(2)and MgO have only a minor effect on the oxidation rates of Al and Ti in the GH984G superalloys.However,it was found that SiO_(2)would intensify the oxidation degree of Al and Ti,and Al was found to become easier oxidized than Ti.Moreover,CaO was found to reduce the activity of SiO_(2)and,thereby,also the oxidation degree of Al and Ti.Also,TiO_(2)was found to reduce the oxidation rate of Ti and instead increase the oxidation rate of Al.Finally,the effect of Al_(2)O_(3)on the oxidation of Al and Ti was observed to be opposite to that of TiO_(2).The calculated results were found to be in good agreement with experimental measurements.Moreover,viscosity experiments showed that CaO would rapidly increase the viscosity of the slag at low temperatures,and that the viscosity of the slag would increase with an increase in SiO_(2)content. 展开更多
关键词 Electroslag remelting withdrawal SLAG GH984G superalloy Oxidation rate VISCOSITY
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Manual reduction with traditional small splints for distal radius fracture in older patients 被引量:4
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作者 Li-You Wei Hong-Wei Zhang +11 位作者 De-Hong Dong Jin-Zeng Zuo Liang Li Guo-Qiang Wang Hua Chen xin geng Cheng Jiao Li-Jun Chen Hui Guo Yu-Long Zhang Lin Rong Jing Zhang 《Journal of Acute Disease》 2021年第2期78-82,共5页
Objective:To investigate the effect of manual reduction with traditional small splints fixation for distal radius fractures in older patients in the emergency department.Methods:Older patients(aged at least 60 years)w... Objective:To investigate the effect of manual reduction with traditional small splints fixation for distal radius fractures in older patients in the emergency department.Methods:Older patients(aged at least 60 years)with distal radius fractures were enrolled in this study.The patients were randomly divided into the treatment group and the control group.The treatment group was treated with manual reduction and small splints fixation.The control group was treated with manual reduction and resin plaster fixation.Before treatment,after reduction,and 3 months after treatment,the palmar tilt angle,ulnar deviation angle,and radial length were recorded.Before treatment and 3 months after treatment,the Cooney wrist joint scores were recorded.The time of fracture healing and related adverse events during the treatment were recorded.Results:Before treatment and after reduction,there were no statistically significant differences between the two groups in palmar tilt angle,ulnar deviation angle,or radial length(P>0.05).Three months after treatment,the palmar tilt angle,ulnar deviation angle,and radial length of the treatment group were better than those of the control group(P<0.05).The Cooney wrist scores of the treatment group was significantly higher than that of the control group three months after the treatment(P<0.05).The time of fracture healing of the treatment group was shorter than that of the control group,but the difference was no statistically significant(P>0.05).Conclusions:Compared with resin plaster fixation,traditional small splints fixation for distal radius fractures in older patients have the advantages of less loss of fracture reduction and faster functional recovery.Besides,the method is simple and low cost thus,it needs to be promoted. 展开更多
关键词 Traditional small splint Distal radius fracture Older patients External fixation
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Effects of current path on structure and segregation during electroslag remelting process of Inconel 718 alloy with same power input 被引量:2
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作者 Fu-bin Liu Hai-bo Cao +2 位作者 Hua-bing Li Zhou-hua Jiang xin geng 《Journal of Iron and Steel Research International》 SCIE EI CSCD 2021年第12期1574-1581,共8页
Current-conductive mold was recently developed to extend electroslag remelting(ESR)functions to overcome some solidification defects by changing the current path.The macrostructures,microstructures,macrosegregation,an... Current-conductive mold was recently developed to extend electroslag remelting(ESR)functions to overcome some solidification defects by changing the current path.The macrostructures,microstructures,macrosegregation,and microsegregation of the Inconel 718 ingots produced by the custom laboratory-scale ESR furnace under different current paths(the classical ESR and the single power,and two circuits ESR process with current-conductive mold(ESR-STCCM))with the same power input were compared and investigated.The results indicate that when the ingot was produced during ESR and ESR-STCCM processes,at the same power input,the pool depth was 104 and 90 mm,respectively.A flatter and shallower molten pool was obtained during ESR-STCCM process.Moreover,compared with a classical ESR ingot,the cooling rate of the centerline of ESR-STCCM ingot was increased from 12.7 to 16.7 K min^(−1).The increased cooling rates caused by decreased melting rate and thinner slag skin reduced the growth angle of columnar crystal to the vertical axis and the secondary dendrite arm spacing.Furthermore,the macrosegregation and microsegregation of segregation elements for ESR-STCCM process were dramatically reduced compared with ESR process.The average volume fraction of Laves phase was reduced from 7.39%to 6.14%,and the segregation of Nb in Laves phase was significantly reduced. 展开更多
关键词 Electroslag remelting Current path STRUCTURE SEGREGATION Inconel 718 alloy Current-conductive mold
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Synthesis of an ordered porous carbon with the dual nitrogen-doped interfaces and its ORR catalysis performance 被引量:2
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作者 Hongwei Zhao Yanqiu Zhang +5 位作者 Li Lixiang xin geng Haiming Yang Weimin Zhou Chengguo Sun Baigang An 《Chinese Chemical Letters》 SCIE CAS CSCD 2021年第1期140-145,共6页
Both nitrogen-doping feature and pore structure are critical factors for developing nitrogen-doped carbons based catalysts with a high performance toward oxygen reduction reaction(ORR).Herein,a simple one-step CVD of ... Both nitrogen-doping feature and pore structure are critical factors for developing nitrogen-doped carbons based catalysts with a high performance toward oxygen reduction reaction(ORR).Herein,a simple one-step CVD of acetylene and acetonitrile vapor method using silanized SBA-15 as a template has been developed to synthesize an ordered porous carbon(OPC) with dual nitrogen-doped interfaces.The optimized sample as prepared with the CVD of 4 h at 750℃ contains two types of ordered mesopores that one type is the ordered cylindrical pores inheriting from the pores of SBA-15 and has a pore width of4.0~5.0 nm,the other type is the ordered quasi-hexagonal pores with a width of 3.0~4.0 nm produced by etching the pore walls of SBA-15.These two types of pores whose pore walls are built by the nitrogen doped carbon layers resulted by the CVD and thus it actually makes the dual nitrogen-doped interfaced OPC(DN-OPC).Meanwhile,DN-OPC contains a few of micropores and a large SSA of 1430 m~2/g.This dualordered pores and dual nitrogen-doped interfaces cannot only facilitate mass transport but also utilize the active sites of DN-OPC for ORR.Therefore,as metal-free ORR catalyst,DN-OPC exhibits a good activity close to commercial Pt/C catalyst,and an excellent durability and methanol tolerance. 展开更多
关键词 Silanized SBA-15 NITROGEN-DOPED Dual-ordered pores CVD of acetonitrile Oxygen reduction reaction
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Measurement of Transverse Tensile Interfacial Strength of REBCO-Coated Conductors 被引量:2
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作者 Peifeng Gao xin geng +2 位作者 Houyuan Zhang Guian Man xingzhe Wang 《Acta Mechanica Solida Sinica》 SCIE EI CSCD 2022年第1期40-50,共11页
We present a new test method for the accurate measurement of the transverse tensile interfacial strength of rare-earth barium copper oxide(REBCO)-coated conductor(CC)tapes to overcome heavy scattering of data tested u... We present a new test method for the accurate measurement of the transverse tensile interfacial strength of rare-earth barium copper oxide(REBCO)-coated conductor(CC)tapes to overcome heavy scattering of data tested using regular test methods.A new composite structure specimen is designed and constructed by solidifying a standard epoxy resin tensile specimen using the three-dimensional printing technology,where a short REBCO CC tape is embedded.The feasibility of the proposed test method is numerically validated through finite element(FE)calculations.Experimental results show that the valid delaminated strength is 2.19-2.51 MPa with the maximum relative error of 7.3%,indicating the elimination of significant scattering in the tested data.By analysing the morphology of the delaminated interfaces and energy-dispersive spectroscopy results,it is discovered that delamination primarily occurs at the interface between the REBCO superconducting layer and the buffer layer and that a small portion of the REBCO and buffer layers peels off.Further error analysis based on the FE method indicates that the tape is more likely to delaminate because of initial defects,whereas the adhesion at the edges of the CC tape due to the redundancy of the epoxy resin increases the resistance of the CC tape to delamination,resulting in a higher testing value than the real one. 展开更多
关键词 REBCO-coated conductor tapes Delamination strength Transverse tension Experimental method Finite element analysis Cohesive zone model
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Regulating interfacial chemistry and kinetic behaviors of F/Mo co-doping Ni-rich layered oxide cathode for long-cycling lithium-ion batteries over-20°C-60°C 被引量:1
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作者 Siqi Guan Lin Tao +9 位作者 Pei Tang Ruopian Fang Huize Wu Nan Piao Huicong Yang Guangjian Hu xin geng Lixiang Li Baigang An Feng Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第7期449-457,共9页
Ni-rich layered oxide cathodes have shown promise for high-energy lithium-ion batteries(LIBs)but are usually limited to mild environments because of their rapid performance degradation under extreme temperature condit... Ni-rich layered oxide cathodes have shown promise for high-energy lithium-ion batteries(LIBs)but are usually limited to mild environments because of their rapid performance degradation under extreme temperature conditions(below0°C and above 50 °C).Here,we report the design of F/Mo co-doped LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(FMNCM)cathode for high-performance LIBs from-20 to 60°C.F^(-) doping with high electronegativity into the cathode surface is found to enhance the stability of surface lattice structure and protect the interface from side reactions with the electrolyte by generating a LiF-rich surface layer.Concurrently,the Mo^(6+) doping suppresses phase transition,which blocks Li^(+)/Ni^(2+) mixing,and stabilizes lithium-ion diffusion pathway.Remarkably,the FMNCM cathode demonstrates excellent cycling stability at a high cutoff voltage of 4.4 V,even at 60°C,maintaining 90.6%capacity retention at 3 C after 150 cycles.Additionally,at temperatures as low as-20°C,it retains 77.1%of its room temperature capacity,achieving an impressive 97.5%capacity retention after 500 cycles.Such stable operation under wide temperatures has been further validated in practical Ah-level pouch-cells.This study sheds light on both fundamental mechanisms and practical implications for the design of advanced cathode materials for wide-temperature LIBs,presenting a promising path towards high-energy and long-cycling LIBs with temperatureadaptability. 展开更多
关键词 Anion-cation co-doping Wide temperature operation Ni-richlayered cathode Phase transition Surface/interface
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Hierarchical pomegranate-structure design enables stress management for volume release of Si anode 被引量:1
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作者 Fang Di Zhenxing Wang +8 位作者 Chong Ge Lixiang Li xin geng Chengguo Sun Haiming Yang Weimin Zhou Dongying Ju Baigang An Feng Li 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2023年第26期1-10,共10页
Si is a promising anode material for lithium-ion batteries owing to its high theoretical capacity.How-ever,large stress during(de)lithiation induces severe structural pulverization,electrical contact failure,and unsta... Si is a promising anode material for lithium-ion batteries owing to its high theoretical capacity.How-ever,large stress during(de)lithiation induces severe structural pulverization,electrical contact failure,and unstable solid-electrolyte interface,which hampers the practical application of Si anode.Herein,a Si-based anode with a hierarchical pomegranate-structure(HPS-Si)was designed to modulate the stress variation,and a sub-micronized Si-based sphere was assembled by the nano-sized Si nanospheres with sub-nanometer-sized multi-phase modification of the covalently linked SiO_(2-x),SiC,and carbon.The sub-micronized HPS-Si stacked with Si nanospheres can avoid agglomerates during cycling due to the high surface energy of nanomaterials.Meanwhile,the reasonable pore structure from SiO_(2) reduction owing to density difference is enough to accommodate the limited volume expansion.The Si spheres with a size of about 50 nm can prevent self-cracking.SiO_(2-x),and SiC as flexible and rigid layers,have been syner-gistically used to reduce the surface stress of conductive carbon layers to avoid cracking.The covalent bonding immensely strengthens the link of the modification with Si nanospheres,thus resisting stress effects.Consequently,a full cell comprising an HPS-Si anode and a LiCoO_(2) cathode achieved an energy density of 415 Wh kg^(-1) with a capacity retention ratio of 87.9%after 300 cycles based on the active ma-terials.It is anticipated that the hierarchical pomegranate-structure design can provide inspiring insights for further studies of the practical application of silicon anode. 展开更多
关键词 Stress management Silicon anode Hierarchical structure Covalent bonding Volume release
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Effect of melt current on multi-physical field and heat flow distribution during ESR process based on model of dynamic formation of slag skin 被引量:1
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作者 Fu-bin Liu xin-hao Yu +3 位作者 Hua-bing Li Zhou-hua Jiang Hong-chun Zhu xin geng 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2023年第6期1258-1267,共10页
A numerical model coupled with a multi-physical field based on dynamic formation of slag skin is established.After validation by comparing the experimental and simulation results of depth of metal pool,slag skin thick... A numerical model coupled with a multi-physical field based on dynamic formation of slag skin is established.After validation by comparing the experimental and simulation results of depth of metal pool,slag skin thickness and melt rate,it is utilized to investigate the effect of melt current on the coupled multi-physical field,slag skin thickness,metal pool depth and the heat flow distribution during electroslag remelting(ESR)Inconel 625 solidification process.The results showed that with the increase in the melt current,the velocities of ESR system and the temperature of metal pool increased,whereas the highest temperature of slag bath firstly decreased and then increased.With the increase in the melt current,the slag skin thickness,metal pool depth and melt rate increased.Furthermore,the characteristics of the heat flow distribution and the effect of melt current on the heat flow distribution were analysed. 展开更多
关键词 Electroslag remelting Melt current Slag skin Model Multi-physical field
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Effects of Ketamine on Basal Gamma Band Oscillation and Sensory Gating in Prefrontal Cortex of Awake Rats 被引量:1
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作者 Renli Qi Jinghui Li +3 位作者 Xujun Wu xin geng Nanhui Chen Hualin Yu 《Neuroscience Bulletin》 SCIE CAS CSCD 2018年第3期457-464,共8页
Gamma band oscillation(GBO) and sensory gating(SG) are associated with many cognitive functions.Ketamine induces deficits of GBO and SG in the prefrontal cortex(PFC). However, the time-courses of the effects of ... Gamma band oscillation(GBO) and sensory gating(SG) are associated with many cognitive functions.Ketamine induces deficits of GBO and SG in the prefrontal cortex(PFC). However, the time-courses of the effects of different doses of ketamine on GBO power and SG are poorly understood. Studies have indicated that GBO power and SG have a common substrate for their generation and abnormalities. In this study, we found that(1) ketamine administration increased GBO power in the PFC in rats differently in the low-and high-dose groups;(2) auditory SG was significantly lower than baseline in the 30 mg/kg and 60 mg/kg groups, but not in the 15 mg/kg and 120 mg/kg groups; and(3) changes in SG and basal GBO power were significantly correlated in awake rats. These results indicate a relationship between mechanisms underlying auditory SG and GBO power. 展开更多
关键词 Gamma band oscillation Sensory gating KETAMINE SCHIZOPHRENIA Parvalbumin-positive basket cell
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Different Frequency Synchronization Theory and Its Frequency Measurement Practice Teaching Innovation Based on Lissajous Figure Method 被引量:1
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作者 xin geng Songlin Li +2 位作者 Guangming Huang Baoqiang Du Jianhua Chen 《Journal of Beijing Institute of Technology》 EI CAS 2018年第2期198-205,共8页
According to the requirement of multi-parameter time and frequency measurement without frequency normalization,a different frequency synchronization theory is proposed based on Lissajous figure method and the variatio... According to the requirement of multi-parameter time and frequency measurement without frequency normalization,a different frequency synchronization theory is proposed based on Lissajous figure method and the variation lawof Lissajous figure which are used in practice teaching of frequency measurement. The theory can achieve high-precision transmission and comparison of time and frequency and precise locking and tracking of phase and frequency,improve the level of scientific research on time and frequency for postgraduate,and promote practice teaching innovation of time frequency measurement for undergraduate. Utilizing the ratio of horizontal and vertical inflection point of the Lissajous figure,the nominal frequency of the measured signal is precisely calculated.The frequency deviation between the measured frequency and its nominal frequency can be obtained by combining the turning cycle of the Lissajous figure. By observing the phase relationship between the frequency standard signal and the measured signal,the accurate measurement of the frequency is implemented. Experimental results showthat the direct measurement and comparison better than the 10-11 order of magnitude with common frequency source can be finished between any signal frequencies.The frequency measurement method based on the theory has the advantage of simple operation,quick measurement speed,small error,lownoise and high measurement precision. It plays an important role in time synchronization,communications,metrology,scientific research,educational technology practice and equipment and other fields. 展开更多
关键词 Lissajous figure different frequency synchronization frequency measurement
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Reaction mechanisms between molten CaF2-based slags and molten 9CrMoCoB steel
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作者 Lei-zhen Peng Zhou-hua Jiang xin geng 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2020年第5期611-619,共9页
Investigating the reaction mechanism between slag and 9CrMoCoB steel is important to develop the proper slag and produce qualified ingots in the electroslag remelting(ESR) process. Equilibrium reaction experiments bet... Investigating the reaction mechanism between slag and 9CrMoCoB steel is important to develop the proper slag and produce qualified ingots in the electroslag remelting(ESR) process. Equilibrium reaction experiments between molten 9CrMoCoB steel and the slags of 55 wt%CaF2–20 wt%CaO–3 wt%MgO–22 wt%Al2O3–xwt%B2O3(x = 0.0, 0.5, 1.0, 1.5, 2.0, 3.0) were conducted. The reaction mechanisms between molten 9 CrMoCoB steel and the slags with different B2O3 contents were deduced based on the composition of the steel and slag samples at different reaction times. Results show that B content in the steel can be controlled within the target range when the B2O3 content is 0.5 wt% and the FeO content ranges from 0.18 wt% to 0.22 wt% in the slag. When the B2O3 content is ≥1 wt%, the reaction between Si and B2O3 leads to the increase of the B content of steel. The additions of SiO2 and B2O3 to the slag should accord to the mass ratio of [B]/[Si] in the electrode, and SiO2 addition inhibits the reaction between Si and Al2O3. 展开更多
关键词 9CrMoCoB ELECTROSLAG REMELTING B2O3 thermodynamic calculation reaction mechanism
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An Approach for Human Posture Recognition Based on the Fusion PSE-CNN-BiGRU Model
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作者 Xianghong Cao xinyu Wang +2 位作者 xin geng Donghui Wu Houru An 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第7期385-408,共24页
This study proposes a pose estimation-convolutional neural network-bidirectional gated recurrent unit(PSECNN-BiGRU)fusion model for human posture recognition to address low accuracy issues in abnormal posture recognit... This study proposes a pose estimation-convolutional neural network-bidirectional gated recurrent unit(PSECNN-BiGRU)fusion model for human posture recognition to address low accuracy issues in abnormal posture recognition due to the loss of some feature information and the deterioration of comprehensive performance in model detection in complex home environments.Firstly,the deep convolutional network is integrated with the Mediapipe framework to extract high-precision,multi-dimensional information from the key points of the human skeleton,thereby obtaining a human posture feature set.Thereafter,a double-layer BiGRU algorithm is utilized to extract multi-layer,bidirectional temporal features from the human posture feature set,and a CNN network with an exponential linear unit(ELU)activation function is adopted to perform deep convolution of the feature map to extract the spatial feature of the human posture.Furthermore,a squeeze and excitation networks(SENet)module is introduced to adaptively learn the importance weights of each channel,enhancing the network’s focus on important features.Finally,comparative experiments are performed on available datasets,including the public human activity recognition using smartphone dataset(UCIHAR),the public human activity recognition 70 plus dataset(HAR70PLUS),and the independently developed home abnormal behavior recognition dataset(HABRD)created by the authors’team.The results show that the average accuracy of the proposed PSE-CNN-BiGRU fusion model for human posture recognition is 99.56%,89.42%,and 98.90%,respectively,which are 5.24%,5.83%,and 3.19%higher than the average accuracy of the five models proposed in the comparative literature,including CNN,GRU,and others.The F1-score for abnormal posture recognition reaches 98.84%(heartache),97.18%(fall),99.6%(bellyache),and 98.27%(climbing)on the self-builtHABRDdataset,thus verifying the effectiveness,generalization,and robustness of the proposed model in enhancing human posture recognition. 展开更多
关键词 Posture recognition mediapipe BiGRU CNN ELU ATTENTION
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Identifi cation of sesquiterpene synthase genes in the genome of Aquilaria sinensis and characterization of anα-humulene synthase
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作者 Jiadong Ran Yuan Li +5 位作者 xin Wen xin geng Xupeng Si Liping Zhang Yimian Ma Zheng Zhang 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第4期1117-1131,共15页
Sesquiterpenes are the major pharmacodynamic components of agarwood,a precious traditional Chinese medicine obtained from the resinous portions of Aquilaria sinensis trees that form in response to environmental stress... Sesquiterpenes are the major pharmacodynamic components of agarwood,a precious traditional Chinese medicine obtained from the resinous portions of Aquilaria sinensis trees that form in response to environmental stressors.To characterize the sesquiterpene synthases responsible for sesquiterpene production in A.sinensis,a bioinformatics analysis of the genome of A.sinensis identifi ed six new terpene synthase genes,and 16 sesquiterpene synthase genes were identifi ed as type TPS-a in a phylogenetic analysis.The expression patterns for eight of the sesquiterpene synthase genes after treatment with various hormones or hydrogen peroxide were analyzed by real-time quantitative PCR.The results suggest that 100μM methyl jasmonate,ethephon,(±)-abscisic acid or hydrogen peroxide could be eff ective short-term eff ectors to increase the expression of sesquiterpene synthase genes,while 1 mM methyl salicylate may have long-term eff ects on increasing the expression of specifi c sesquiterpene synthase genes(e.g.,As-SesTPS,AsVS,AsTPS12 and AsTPS29).The expression changes in these genes under various conditions refl ected their specifi c roles during abiotic or biotic stresses.Heterologous expression of a novel A.sinensis sesquiterpene synthase gene,AsTPS2,in Escherichia coli produced a major humulene product,so AsTPS2 is renamed AsHS1.AsHS1 is diff erent from ASS1,AsSesTPS,and AsVS,for mainly producingα-humulene.Based on the predicted space conformation of the AsHS1 model,the small ligand molecule may bind to the free amino acid by hydrogen bonding for the catalytic function of the enzyme,while the substrate farnesyl diphosphate(FPP)probably binds to the free amino acid on one side of the RxR motif.Arg450,Asp453,Asp454,Thr457,and Glu461 from the NSE/DTE motif and D307 and D311 from the DDxxD motif were found to form a polar interaction with two Mg^(2+)clusters by docking.The Mg^(2+)-bound DDxxD and NSE/DTE motifs and the free RXR motif are jointly directed into the catalytic pocket of AsHS1.Comparison of the tertiary structural models of AsHS1 with ASS1 showed that they diff ered in structures in several positions,such as surrounding the secondary catalytic pocket,which may lead to diff erences in catalytic products.Based on the results,biosynthetic pathways for specifi c sesquiterpenes such asα-humulene in A.sinensis are proposed.This study provides novel insights into the functions of the sesquiterpene synthases of A.sinensis and enriches knowledge on agarwood formation. 展开更多
关键词 AGARWOOD Aquilaria sinensis Sesquiterpene synthase Humulene
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Clinical Report on Californium-252 Neutron Intraluminal Brachytherapy Combined with External Irradiation for Cervical Carcinoma Treatment
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作者 Huanyu Zhao Keming Wang +2 位作者 Jian Sun xin geng Weiming Zhang 《Chinese Journal of Clinical Oncology》 CSCD 2006年第5期337-342,共6页
OBJECTIVE To observe the curative effects and complications of californium-252 (^252Cf) neutron intraluminal brachytherapy (IBT) combined with external irradiation (El) for treatment of cervical carcinoma.METHOD... OBJECTIVE To observe the curative effects and complications of californium-252 (^252Cf) neutron intraluminal brachytherapy (IBT) combined with external irradiation (El) for treatment of cervical carcinoma.METHODS From December 2000 to December 2004, 128 cases of cer vical carcinoma staged into IIA-IIIB according to the International Federation of Gynecology and Obstetrics (FIGO) standards were treated with ^252Cf neutron IBT using 8-10 Gy per fraction, once a week. The total dose at reference A point was 36-40 Gy in 4-5 fractions. From the second day after ^252Cf neutron IBT treatment, the whole pelvic cavity was treated with ^60Co y-ray El, applying 2 Gy per fraction, 4 times per week. After 20-25Gy of El, the center of the whole pelvic field was blocked with 4 cm of lead in width. The total dose of El was 45-50 Gy.RESULTS The short-term therapeutic effects were CR 95.3% and PR 4.7%. The 3 and 5-year local control rates were 93.5% and 87.9%. The overall 3-year survival rate was 87.5% and for Stages Ⅱ and Ⅲ , 90.9% and 81.5% respectively; the overall 5-year survival rate was 70% and for Stages II and III, 76.2% and 61% respectively. The rate of radiation complications was 4.7% for radiation cystitis, 7.8% for radiation proctitis, 6.3% for vagina contracture and adhesion and 5.5% for protracted radiation proctitis.CONCLUSION An combination of ^252Cf neutron IBT with El for treatment of cervical carcinoma can be well-tolerated by cervical carcinoma patients. The rate of local tumor control is high and radiation complications are few. 展开更多
关键词 califomium-252 neutron BRACHYTHERAPY RADIOTHERAPY cervical carcinoma.
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Hydrological Process Analysis in Earth Dams Using the PCSiWaPro as a Basis for Stability Analysis
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作者 Jinxing Guo Rene Blankenburg +1 位作者 xin geng Peter-Wolfgang Graeber 《Journal of Geological Resource and Engineering》 2017年第3期139-145,共7页
Earth dam is always a safety issue, as it can experience catastrophic destruction due to the slope failure caused by various factors, such as water content increasing in earth slopes, vegetation root decay and so on. ... Earth dam is always a safety issue, as it can experience catastrophic destruction due to the slope failure caused by various factors, such as water content increasing in earth slopes, vegetation root decay and so on. This study is to investigate the variation of hydrological processes in the saturated and partially saturated slopes with a new simulation program PCSiWaPro (a computer aided leachate forecast tool) under transient boundary conditions. The integration of a weather generator inside the PCSiWaPro allows a transient water flow calculation with respect to atmospheric conditions (precipitation, daily mean temperature and sunshine duration) and removal of water by plant roots and leaves. The simulation results of one scenario in a Chinese earth dam clearly demonstrate a good applicability of the program PC S iWaPro. 展开更多
关键词 Earth dam water balance seepage line VEGETATION precipitation.
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