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Use of supervised and unsupervised approaches to make zonal application maps for variable-rate application of crop growth regulators in commercial cotton fields
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作者 ANDREA Maria C.da S. OLIVEIRA Cristiano F.de +7 位作者 MOTA Fabrícia C.M. SANTOS Rafael C.dos RODRIGUES JUNIOR Edilson F. BIANCHI Lucas M. OLIVEIRA Rodrigo S.de GOUVEIA Caio M.de BARBOSA Victor G.S. BISPO E SILVA Marco A. 《Journal of Cotton Research》 2025年第1期1-20,共20页
Background Zonal application maps are designed to represent field variability using key variables that can be translated into tailored management practices.For cotton,zonal maps for crop growth regulator(CGR)applicati... Background Zonal application maps are designed to represent field variability using key variables that can be translated into tailored management practices.For cotton,zonal maps for crop growth regulator(CGR)applications under variable-rate(VR)strategies are commonly based exclusively on vegetation indices(VIs)variability.However,VIs often saturate in dense crop vegetation areas,limiting their effectiveness in distinguishing variability in crop growth.This study aimed to compare unsupervised framework(UF)and supervised framework(SUF)approaches for generat-ing zonal application maps for CGR under VR conditions.During 2022-2023 agricultural seasons,an UF was employed to generate zonal maps based on locally collected field data on plant height of cotton,satellite imagery,soil texture,and phenology data.Subsequently,a SUF(based on historical data between 2020-2021 to 2022-2023 agricultural seasons)was developed to predict plant height using remote sensing and phenology data,aiming to replicate same zonal maps but without relying on direct field measurements of plant height.Both approaches were tested in three fields and on two different dates per field.Results The predictive model for plant height of SUF performed well,as indicated by the model metrics.However,when comparing zonal application maps for specific field-date combinations,the predicted plant height exhibited lower variability compared with field measurements.This led to variable compatibility between SUF maps,which utilized the model predictions,and the UF maps,which were based on the real field data.Fields characterized by much pronounced soil texture variability yielded the highest compatibility between the zonal application maps produced by both SUF and UF approaches.This was predominantly due to the greater consistency in estimating plant development patterns within these heterogeneous field environments.While VR application approach can facilitate product savings during the application operation,other key factors must be considered.These include the availability of specialized machinery required for this type of applications,as well as the inherent operational costs associated with applying a single CGR product which differs from the typical uniform rate applications that often integrate multi-ple inputs.Conclusion Predictive modeling shows promise for assisting in the creation of zonal application maps for VR of CGR applications.However,the degree of agreement with the actual variability in crop growth found in the field should be evaluated on a field-by-field basis.The SUF approach,which is based on plant heigh prediction,demonstrated potential for supporting the development of zonal application maps for VR of CGR applications.However,the degree to which this approach aligns itself with the actual variability in crop growth observed in the field may vary,necessi-tating field-by-field evaluation. 展开更多
关键词 Cotton Site-specific management Crop growth regulator Unsupervised framework Supervised framework Zonal application maps
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Dynamic response characteristics of metal cylindrical shell driven by explosive charge with waveform regulator
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作者 Weixin Bi Weibing Li +2 位作者 Junbao Li Heyang Xu Wenbin Li 《Defence Technology(防务技术)》 2025年第10期84-99,共16页
Waveform regulator in charge is a method that can realize multi-source detonation wave superposition through a single point detonation.The method does not need to weaken the strength of shell,and relies on the high st... Waveform regulator in charge is a method that can realize multi-source detonation wave superposition through a single point detonation.The method does not need to weaken the strength of shell,and relies on the high stress generated by superposition to cut shell into regular fragments.Additionally,it can be combined with different initiation methods to alter the fragmentation outcomes.In this study,aiming at the fracture strain of metal cylindrical shell driven by explosive charge with waveform regulator,theoretical analysis was first adopted to obtain the prediction model of the fracture strain of cylindrical shell with waveform regulator and the model of the axial distribution of the stress concentration factor.On this basis,both theoretical analysis and numerical models were utilized to investigate the effect of waveform regulator on the initial velocity of fragments.Finally,experiments were conducted to validate the fracture strain prediction model for cylindrical shell with waveform regulator.The research results show that the collision angles of the detonation waves at different axial positions are different,which leads to the stress concentration factor on the shell presenting a trend of gradually decreasing,then sharply increasing,and then rapidly decreasing along the axial direction.Additionally,the changes in the slot spacing and the thickness of outer charge will also affect the stress concentration factor,and the influence of outer charge thickness is relatively large.The smaller the ratio of charge volume to waveform regulator volume,the larger the axial sparse wave intensity and the more the fragment initial velocity decrease.From the initiation end to the non-initiation end,the failure modes of the shell sequentially change from pure shear,to mixed tensile-shear,and finally to pure tensile failure.The experimental results are in good agreement with the calculated results of the fracture strain model,and the maximum relative error is less than 10%,which indicates that the fracture strain prediction model of the cylindrical shell with waveform regulator established in this paper by considering the increase of elastic energy per unit volume caused by stress concentration on the shell is reliable. 展开更多
关键词 Cylindrical shell Waveform regulator Stress concentration Fracture strain
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An overview of pigment gland morphogenesis and its regulatory mechanism
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作者 SUN Yue YANG Ping +5 位作者 HAN Yifei LI Huazu SUN Deli CHEN Jinhong ZHU Shuijin ZHAO Tianlun 《Journal of Cotton Research》 CAS 2024年第2期207-214,共8页
Cotton has enormous economic potential,providing high-quality protein,oil,and fibre.But the comprehensive utilization of cottonseed is limited by the presence of pigment gland and its inclusion.Pigment gland is a comm... Cotton has enormous economic potential,providing high-quality protein,oil,and fibre.But the comprehensive utilization of cottonseed is limited by the presence of pigment gland and its inclusion.Pigment gland is a common characteristic of Gossypium genus and its relatives,appearing as visible dark opaque dots in most tissues and organs of cotton plants.Secondary metabolites,such as gossypol,synthesized and stored in the cavities of pigment glands act as natural phytoalexins,but are toxic to humans and other monogastric animals.However,only a few cotton genes have been identified as being associated with pigment gland morphogenesis to date,and the developmental processes and regulatory mechanism involved in pigment gland formation remain largely unclear.Here,the research progress on the process of pigment gland morphogenesis and the genetic basis of cotton pigment glands is reviewed,for providing a theoretical basis for cultivating cotton with the ideal pigment gland trait. 展开更多
关键词 Cotton Pigment gland morphogenesis Transcriptional regulation Terpenoids biosynthesis
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Research on DSP-Based Automatic Excitation Regulator in Small Rural Hydropower Station 被引量:1
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作者 Gu Xiang-yu Zhao Yu-lin +2 位作者 Fu Yan Zhang Yu-juan Sun Shuai 《Journal of Northeast Agricultural University(English Edition)》 CAS 2013年第1期65-69,共5页
Excitation regulator has played an important role to ensure that generator run safely and stably. However, in some remote areas, the rural small generator excitation control system is very backward, and it has hindere... Excitation regulator has played an important role to ensure that generator run safely and stably. However, in some remote areas, the rural small generator excitation control system is very backward, and it has hindered the development of Chinese agriculture and the pace of new countryside construction. This paper introduced a kind of structure and basic principle of DSP-based automatic excitation regulator, which was applied to rural small generator. We chose TMS320LF2407A chip as the core of regulator control system; the regulator adjusted PWM based on PID control strategy to control the exciting current. The theoretical analysis showed that the regulator had the characteristics of simplicity and reliability, well dynamic and static characteristics, and it could also adjust its own state quickly. The result was applicable to small rural hydropower station. 展开更多
关键词 DSP PID control strategy automatic excitation regulator new countryside construction
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Influences of Plant Growth Regulators, Basal Media and Carbohydrate Levels on Cell Suspension Culture of Panax ginseng 被引量:1
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作者 Tang Wei Wu Jiongyuan, Zhang Limei(Northeast Agricultural University, Harbin 150030, P R C) 《Journal of Northeast Agricultural University(English Edition)》 CAS 1995年第1期62-65,共4页
A cell suspension culture of Panax ginseng which may be continuously subcultured has been established. Embryogenic callus derived from clutured young leaves was used to initiate the culture.Plant growth regulators, ba... A cell suspension culture of Panax ginseng which may be continuously subcultured has been established. Embryogenic callus derived from clutured young leaves was used to initiate the culture.Plant growth regulators, basal medium formula and carbohydrate levels were examined to determine their various effects on suspension culture cell growth and development. The best selection of plant growth regulator, hasal medium and carbohydrate level is 2 mg / L 2,4-D: 0.5 mg / L KT,MS and 3% sucrose respectively. 展开更多
关键词 Panax ginseng cell suspension culture plant growth regulators
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Adjusting the Parameters of PI Regulator in All-electrical Tank Gun Control System by Computer Program
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作者 臧克茂 贺跃 +1 位作者 李匡成 李长兵 《Defence Technology(防务技术)》 SCIE EI CAS 2005年第2期140-145,共6页
Both the traverse subsystem and the elevation subsystem of the all-electrical tank gun control system are composed of electrical drive control system respectively. The parameters of PI regulator in these electrical dr... Both the traverse subsystem and the elevation subsystem of the all-electrical tank gun control system are composed of electrical drive control system respectively. The parameters of PI regulator in these electrical drive control systems affect the performance of the control system seriously. Up to now, there is not a simple and practical method for choosing regulator parameters, which are usually determined by repeated and continual readjustment. This method is low efficient, and the parameters got are not always optimal. A method for on-line adjusting the parameters of PI regulator in the electrical drive control system by computer program is introduced in this paper. The function of adjusting PI parameters of the electrical drive control system is realized by PC program written by VC++ and controlling program written by assemble language and by the communication between PC and DSP completed by the control MSCOMM in VC++6.0. The method as mentioned above which is applied for an all-electrical tank gun control system under development is proved very available, a better performance might be obtained for the all-electrical tank gun control system easily. 展开更多
关键词 PI regulator SERIAL communication all-electrical TANK GUN control system
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The Design of Digital Excitation Regulator
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作者 TIZong-li ZHAOYu-lin 《Journal of Northeast Agricultural University(English Edition)》 CAS 2001年第1期49-54,共6页
The digital excitation regulator is very popular in the small electric plant. This kind of regulator can im- prove the working condition of generator and its working efficiency. It is on the base of the 80C51 Micro-co... The digital excitation regulator is very popular in the small electric plant. This kind of regulator can im- prove the working condition of generator and its working efficiency. It is on the base of the 80C51 Micro-con- troller. The regulator can automatically finish some functions through the combination of software and hard- ware. Through the experiment we can know it is more intellectual than the traditional analog excitation regu- lator. 展开更多
关键词 Digital excitation regulator 80C51 Micro-controller ANALOG
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Regulatory puzzle of xyn1 gene (xylanase1) expression in Trichoderma reesei
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作者 Robert L Mach Elisabeth Würleitner +2 位作者 Astrid R Stricker Roman Rauscher Christian Wacenovsky 《浙江大学学报(农业与生命科学版)》 CAS CSCD 北大核心 2004年第4期431-431,共1页
Xylanase 1 (Xyn1) is one of the two major representatives of the xylanase system of T. reesei; the mechanisms governing its expression were analysed throughout this study. All factors and regulatory motifs responsible... Xylanase 1 (Xyn1) is one of the two major representatives of the xylanase system of T. reesei; the mechanisms governing its expression were analysed throughout this study. All factors and regulatory motifs responsible for transcriptional regulation and the model of their interplay in induction and repression will be presented. Using in vivo foot printing analysis of xylan-induced and glucose repressed mycelia, we detected three adjacent nucleotide sequences contacted by DNA-binding proteins. Protection within the inverted repeat of the Cre1 (SYGGRG) consensus sequence on the non coding strand under repressing conditions is in perfect agreement with the previously reported Cre1 dependent glucose repression of xyn1. Constitutive protein binding could be observed to a CCAAT-box and an inverted repeat of a 5′ GGCTAA 3′ sequence. EMSA with crude extracts from induced and repressed mycelia revealed that the latter motifs are sufficient for formation of the basal transcriptional complex under all conditions. The inverted repeat of GGCTAA closely resembles the consensus sequences of the cellulase and xylanase regulators Ace1, Ace2 and, Xyr1 (encoded by xyr1, cloned and characterised in this study) EMSA with heterologously expressed components of each factor and of the T. reesei Hap2/3/5 protein complex revealed that the basal transcriptional complex is formed by Xyr1 and the Hap2/3/5. Additionally to the Cre1 mediated carbon catabolite repression a yet unknown mechanism antagonizing induction of xyn1 expression could be elucidated. Latter occurs through competition of the repressor Ace1 and Xyr1 for the GGCTAA motif. In vivo proof for the relevance of identified motifs could be given through analysis of T. reesei transformants containing correspondingly mutated versions of the xyn1 promoter fused to the A. niger goxA gene. The results indicated that the basal as well as the induction level of xyn1 gene transcription is dependent on an interaction of Xyr1 with the GGCTAA motif while formation of the CCAAT-Hap2/3/5 complex slightly reduces induction. It can be concluded that mutations impairing protein binding in vitro lead to a loss of distinct regulatory functions in xyn1 gene expression in vivo. A respective model of gene regulation will be presented. 展开更多
关键词 TRICHODERMA gene regulation xylanase1 transcriptional factors
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Carbon materials for smart batteries
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作者 ZHOU Jun-yi DU Hong-hui +2 位作者 WANG Xue-tao CAO Xin-ru ZHI Lin-jie 《新型炭材料(中英文)》 北大核心 2025年第4期822-836,共15页
Smart batteries play a key role in upgrading energy storage systems.However,they require a well-balanced integration of material structure,functional properties,and electrochemical performance,and their development is... Smart batteries play a key role in upgrading energy storage systems.However,they require a well-balanced integration of material structure,functional properties,and electrochemical performance,and their development is limited by conventional material systems in terms of energy density,response time,and functional integration.Carbon materials have emerged as a key solution for overcoming these problems due to their structural adjustability and multifunctional compatibility.Strategies for improving their electrochemical performance by changing the pore structure and interlayer spacing,as well as chemical functionalization,and composite design are analyzed,and their impact on improving the specific capacity and cycling stability of batteries is demonstrated.The unique advantages of carbon materials in realizing smart functions such as power supply,real-time monitoring and energy management in smart batteries are also discussed.Based on current progress in related fields,the prospects for the use of carbon materials in smart batteries are evaluated. 展开更多
关键词 Carbon materials Smart battery Structural regulation Electrochemical performance Multifunctional integration
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Structure Regulation Engineering for Biomass-Derived Carbon Anodes Enabling High-Rate Dual-Ion Batteries
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作者 Rui Zhou Rui Liu +4 位作者 Yun-Nuo Li Si-Jie Jiang Tian-Tian Jing Yan-Song Xu Fei-Fei Cao 《电化学(中英文)》 北大核心 2025年第8期34-43,共10页
Dual-ion batteries(DIBs)usually use carbon-based materials as electrodes,showing advantages in high operating volt-age,potential low cost,and environmental friendliness.Different from conventional“rocking chair”type... Dual-ion batteries(DIBs)usually use carbon-based materials as electrodes,showing advantages in high operating volt-age,potential low cost,and environmental friendliness.Different from conventional“rocking chair”type secondary batter-ies,DIBs perform a unique working mechanism,which employ both cation and anion taking part in capacity contribution at an anode and a cathode,respectively,during electrochemical reactions.Graphite has been identified as a suitable cathode material for anion intercalation at high voltages(>4.8 V)with fast reaction kinetics.However,the development of DIBs is being hindered by dynamic mismatch between a cathode and an anode due to sluggish Li+diffusion at a high rate.Herein,we prepared phyllostachys edulis derived carbon(PEC)through microstructure regulation strategy and investigated the carbonized temperature effect,which effectively tailored the rich short-range ordered graphite microdomains and disor-dered amorphous regions,as well as a unique nano-pore hierarchical structure.The pore size distribution of nano-pores was concentrated in 0.5-5 nm,providing suitable channels for rapid Li+transportation.It was found that PEC-500(carbon-ized at 500℃)achieved a high capacity of 436 mAh·g^(-1)at 300 mA·g^(-1)and excellent rate performance(maintaining a high capacity of 231 mAh·g^(-1)at 3 A·g^(-1)).The assembled dual-carbon PEC-500||graphite full battery delivered 114 mAh·g^(-1)at 10 C with 96%capacity retention after 3000 cycles and outstanding rate capability,providing 74 mAh·g^(-1)at 50 C. 展开更多
关键词 Dual-ion battery Biomass hard carbon Structural regulation High operating voltage High rate
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Tailoring the pore structure of hard carbon for enhanced sodium-ion battery anodes
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作者 SONG Ning-Jing MA Can-liang +3 位作者 GUO Nan-nan ZHAO Yun LI Wan-xi LI Bo-qiong 《新型炭材料(中英文)》 北大核心 2025年第2期377-391,共15页
Biomass-derived hard carbons,usually prepared by pyrolysis,are widely considered the most promising anode materials for sodium-ion bat-teries(SIBs)due to their high capacity,low poten-tial,sustainability,cost-effectiv... Biomass-derived hard carbons,usually prepared by pyrolysis,are widely considered the most promising anode materials for sodium-ion bat-teries(SIBs)due to their high capacity,low poten-tial,sustainability,cost-effectiveness,and environ-mental friendliness.The pyrolysis method affects the microstructure of the material,and ultimately its so-dium storage performance.Our previous work has shown that pyrolysis in a sealed graphite vessel im-proved the sodium storage performance of the car-bon,however the changes in its microstructure and the way this influences the sodium storage are still unclear.A series of hard carbon materials derived from corncobs(CCG-T,where T is the pyrolysis temperature)were pyrolyzed in a sealed graphite vessel at different temperatures.As the pyrolysis temperature increased from 1000 to 1400℃ small carbon domains gradually transformed into long and curved domains.At the same time,a greater number of large open pores with uniform apertures,as well as more closed pores,were formed.With the further increase of pyrolysis temperature to 1600℃,the long and curved domains became longer and straighter,and some closed pores gradually became open.CCG-1400,with abundant closed pores,had a superior SIB performance,with an initial reversible ca-pacity of 320.73 mAh g^(-1) at a current density of 30 mA g^(-1),an initial Coulomb efficiency(ICE)of 84.34%,and a capacity re-tention of 96.70%after 100 cycles.This study provides a method for the precise regulation of the microcrystalline and pore structures of hard carbon materials. 展开更多
关键词 Pore structure regulation Closed pore Corn cob Hard carbon anode material Sodium-ion batteries
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Effects of Different Exogenous Substances on Seed Germination of Isatis indigotica Under Drought Stress and Chemical Composition of Isatis indigotica leaves
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作者 Wang Hao Qin Jingjing +4 位作者 Shi Zhe Song Jiayao Ma Wuqiong Wang Huimin Cao Jinjun 《Journal of Northeast Agricultural University(English Edition)》 CAS 2024年第2期66-75,共10页
This study was to investigate the effects of three exogenous substances on chemical constituents of Isatis indigotica leavesand their efficacy in alleviating drought stress, and explore the methods of applying exogeno... This study was to investigate the effects of three exogenous substances on chemical constituents of Isatis indigotica leavesand their efficacy in alleviating drought stress, and explore the methods of applying exogenous substances to efficient cultivationof Isatis indigotica. Polyethylene glycol (PEG) was used to simulate drought stress to deal with seeds of Isatis indigotica at thegermination stage (concentration: 0, 10%, 15%, and 20%). Simultaneous operation of exogenous growth regulators [microbialinoculum (MI), γ-aminobutyric acid (GABA) and salicylic acid (SA)] and PEG were implemented in seeds of Isatis indigotica.The effects of drought stress and the mitigation of exogenous substances were observed by statistics of seed germination potential,germination rate, hypocotyl length, and radicle length of each treatment. The effects of exogenous substances on the content ofalkaloids, crude protein and free amino acids in the leaves of Isatis indigotica grown in a greenhouse were determined after sprayingexogenous substances on the plants. The differences of germination potential, germination rate, hypocotyl length, and radicle lengthamong 15% PEG stress treatment, 10% PEG stress treatment and the control were significant (P<0.05). According to the predesignedgermination standard, the seeds did not germinate under 20% PEG stress treatment. When the PEG concentration was 15%, the resultsof seed germination potential and germination rate after adding MI were significantly different from those under stress alone (P<0.05).When exposed to 10% PEG stress, the supplementation of GABA led to a notable increase in radicle length of Isatis indigotica seeds,showing significant differences compared to other three treatments. The application of MI and GABA under 15% PEG stress resultedin a significant increase in the radicle and hypocotyl length of Isatis indigotica seeds compared to other two treatments. The contentof the total alkaloids in leaves of Isatis indigotica was significantly increased after spraying GABA. Meanwhile, the contents of crudeprotein and the total free amino acids were kept constant after spraying exogenous substances. Application of MI and GABA couldalleviate drought stress of Isatis indigotica. The content of the total alkaloids in leaves of Isatis indigotica could significantly increaseafter spraying GABA. 展开更多
关键词 Isatis indigotica Fort. exogenous growth regulator drought stress chemical composition leaves of Isatis indigotica
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Three-channel CMOS transimpedance amplifier for LiDAR sensor receiver 被引量:1
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作者 LIU Ruqing ZHU Jingguo +3 位作者 JIANG Yan LI Feng JIANG Chenghao MENG Zhe 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2024年第1期74-80,共7页
For time-of-flight(TOF)light detection and ranging(LiDAR),a three-channel high-performance transimpedance amplifier(TIA)with high immunity to input load capacitance is presented.A regulated cascade(RGC)as the input st... For time-of-flight(TOF)light detection and ranging(LiDAR),a three-channel high-performance transimpedance amplifier(TIA)with high immunity to input load capacitance is presented.A regulated cascade(RGC)as the input stage is at the core of the complementary metal oxide semiconductor(CMOS)circuit chip,giving it more immunity to input photodiode detectors.A simple smart output interface acting as a feedback structure,which is rarely found in other designs,reduces the chip size and power consumption simultaneously.The circuit is designed using a 0.5μm CMOS process technology to achieve low cost.The device delivers a 33.87 dB?transimpedance gain at 350 MHz.With a higher input load capacitance,it shows a-3 dB bandwidth of 461 MHz,indicating a better detector tolerance at the front end of the system.Under a 3.3 V supply voltage,the device consumes 5.2 mW,and the total chip area with three channels is 402.8×597.0μm2(including the test pads). 展开更多
关键词 transimpedance amplifier(TIA) three-channel regulated cascade(RGC) light detection and ranging(LiDAR)
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Effects of anions on the structural regulation of Zn‑salen‑modified metal‑organic cage
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作者 GUO Qiaojia CAI Junkai DUAN Chunying 《无机化学学报》 SCIE CAS CSCD 北大核心 2024年第11期2203-2211,共9页
By virtue of a 3∶1 complementary coordination strategy,a chiral heteroleptic metal-organic cage that con-tains divergent functional units,Pd‑R(Zn),was precisely constructed via self-assembly of monodentate variationa... By virtue of a 3∶1 complementary coordination strategy,a chiral heteroleptic metal-organic cage that con-tains divergent functional units,Pd‑R(Zn),was precisely constructed via self-assembly of monodentate variational Zn-salen ligands RZn and NADH(reduced nicotinamide adenine dinucleotide)mimic modified tridentate ligands with square-planar Pd ions.UV-Vis and luminescence spectra experiments reveal that different anions could selec-tively interact with different sites of Zn-salen modified metal-organic cages to achieve the structural regulation of cage compound,by using the differentiated host-guest electrostatic interactions of counter ions with metal-organic hosts.Compared to other anions,the presence of chloride ions caused the most significant fluorescence emission enhancement of Pd‑R(Zn),meanwhile,the UV-Vis absorption band attributed to the salen aromatic backbone showed an absorption decrease,and the metal-to-ligand induced peak displayed a blue shift effect.Circular dichro-ism and ^(1)H NMR spectra further demonstrate that the introduction of chloride anions is beneficial to keeping a more rigid scaffold. 展开更多
关键词 metal-organic cage Zn-salen host-guest electrostatic interaction ANIONS structural regulation
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Sorbitol-Electrolyte-Additive Based Reversible Zinc Electrochemistry
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作者 Qiong Sun Hai-Hui Du +5 位作者 Tian-Jjiang Sun Dian-Tao Li Min Cheng Jing Liang Hai-Xia Li Zhan-Liang Tao 《电化学(中英文)》 CAS 北大核心 2024年第7期28-37,共10页
The unstable zinc(Zn)/electrolyte interfaces formed by undesired dendrites and parasitic side reactions greatly hinder the development of aqueous zinc ion batteries.Herein,the hydroxy-rich sorbitol was used as an addi... The unstable zinc(Zn)/electrolyte interfaces formed by undesired dendrites and parasitic side reactions greatly hinder the development of aqueous zinc ion batteries.Herein,the hydroxy-rich sorbitol was used as an additive to reshape the solvation structure and modulate the interface chemistry.The strong interactions among sorbitol and both water molecules and Zn electrode can reduce the free water activity,optimize the solvation shell of water and Zn^(2+)ions,and regulate the formation of local water(H_(2)O)-poor environment on the surface of Zn electrode,which effectively inhibit the decomposition of water molecules,and thus,achieve the thermodynamically stable and highly reversible Zn electrochemistry.As a result,the assembled Zn/Zn symmetric cells with the sorbitol additive realized an excellent cycling life of 2000 h at 1 mA·cm^(-2)and 1 mAh·cm^(-2),and over 250 h at 5 mA.cm^(-2)and 5 mAh.cm^(-2).Moreover,the Zn/Cu asymmetric cells with the sorbitol additive achieved a high Coulombic efficiency of 99.6%,obtaining a better performance than that with a pure 2 mol-L^(-1)ZnSO_(4)electrolyte.And the constructed Zn/poly1,5-naphthalenediamine(PNDA)batteries could be stably discharged for 2300 cycles at 1 A g^(-1)with an excellent capacity retention rate.This result indicates that the addition of 1 mol-L^(-1)non-toxic sorbitol into a conventional ZnSO_(4)electrolyte can successfully protect the Zn anode interface by improving the electrochemical properties of Zn reversible deposition/decomposition,which greatly promotes its cycle performance,providing a new approach in future development of high performance aqueous Zn ion batteries. 展开更多
关键词 Aqueous zinc ion batteries DENDRITE Sorbitol additive Solvation regulation Interface modulation
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一种气动/电磁联合作动的主动隔振器设计与仿真 被引量:4
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作者 李斌 董万元 王小兵 《西北工业大学学报》 EI CAS CSCD 北大核心 2013年第6期871-877,共7页
大型机载光学系统要求有非常高的光束指向控制精度,这将给机载隔振平台的设计提出若干新的挑战。从分析飞机结构振动特点出发,提出采用气动与电磁驱动联合作动的方法,为飞机平台设计一种适合大型机载光学系统安装的主动隔振器。单个... 大型机载光学系统要求有非常高的光束指向控制精度,这将给机载隔振平台的设计提出若干新的挑战。从分析飞机结构振动特点出发,提出采用气动与电磁驱动联合作动的方法,为飞机平台设计一种适合大型机载光学系统安装的主动隔振器。单个隔振器的承载能力为150~190 kg ,垂向隔振频带范围为1~100 Hz,最大输出控制力为560 N。文中阐明了气动/电磁联合作动的运行机理,并对隔振器进行了结构详细设计;然后对隔振器进行数学模型简化,建立隔振器的动力学方程;最后利用PID控制算法和LQR控制算法,对隔振器进行Matlab/Simulink数值仿真。仿真结果表明所设计的隔振器隔振性能优异,在垂向宽带(1~100 Hz)大振幅随机扰动作用下,可以将有效载荷的振动位移控制到±10μm量级,能够满足光学设备的安装要求。 PID方法和LQR方法的控制效果对比表明,对于单个隔振器系统,PID方法较LQR方法易于实现,并且控制效果也略优。 展开更多
关键词 空气弹簧 电磁驱动 PID(proportion-integral derivative) LQR(1inear QUADRATIC regulator) 机载光学平台
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不同生长调节剂对新美人指葡萄延后效果的影响 被引量:8
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作者 程媛媛 陶建敏 谢周 《江西农业学报》 CAS 2010年第10期42-44,共3页
以新美人指葡萄为试材,于果实发育中期(7月18日)分别用5mg/LCPPU,25mg/LGA3+5mg/LCPPU,100mg/LNAA及25mg/LGA3浸蘸果穗。在果实处理后109d采样,研究了不同处理对葡萄单果重、硬度、可溶性固形物含量及糖酸等指标的影响。结果表明,各处... 以新美人指葡萄为试材,于果实发育中期(7月18日)分别用5mg/LCPPU,25mg/LGA3+5mg/LCPPU,100mg/LNAA及25mg/LGA3浸蘸果穗。在果实处理后109d采样,研究了不同处理对葡萄单果重、硬度、可溶性固形物含量及糖酸等指标的影响。结果表明,各处理均能不同程度地延迟果实成熟,与对照均有一定差异。其中以25mg/LGA3+5mg/LCPPU的延后效果最好,可溶性固形物、糖酸等指标均与对照差异性最大,其中果实处理后109d可溶性固形物含量、可溶性糖含量及可滴定酸含量分别是对照的66.76%、59.05%和173.50%,并在后期单果重、固形物及含糖量均有较大增长,接近对照。 展开更多
关键词 生长调节剂 美人指葡萄 后效 Plant Growth regulators Different 可溶性固形物含量 果实处理 可溶性糖含量 单果重 CPPU GA3 指标 糖酸 果实发育 果实成熟 差异性 不同处理 酸含量 含糖量 硬度
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线性二次型调节器算法对黏弹性阻尼器参数的优化设计
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作者 邹旭岩 宋荣方 《科学技术与工程》 北大核心 2014年第9期236-239,共4页
鉴于黏弹性阻尼器(VED)对结构减震控制的局限性,采用等效刚度和等效阻尼的力学模型,对VED的参数优化问题进行了研究。基于LQR的最优控制算法,提出一种以VED控制下结构的振动响应去逼近最优控制下结构振动响应的VED参数优化的新方法。通... 鉴于黏弹性阻尼器(VED)对结构减震控制的局限性,采用等效刚度和等效阻尼的力学模型,对VED的参数优化问题进行了研究。基于LQR的最优控制算法,提出一种以VED控制下结构的振动响应去逼近最优控制下结构振动响应的VED参数优化的新方法。通过对一个加入VED的3层混凝土框架结构进行动力响应数值分析,得出结论。方法相对简单,所提出的VED参数优化方法能够使结构动力响应得到有效的控制,控制效果与采用最优控制算法的计算结果较为接近,验证了该方法的有效性。利用上述方法优化VED参数,对结构进行振动控制,虽然无法达到全状态最优增益反馈控制力的主动控制效果,但经过优化后的动力反应逼近最优控制算法的结果。该方法为VED在结构减震控制方面取得更好的减震效果提供了理论参考。 展开更多
关键词 黏弹性阻尼器 参数优化 线性二次型调节器(1inear QUADRATIC regulator LQR)算法 振动控制
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中药益糖康干预并有糖调节受损的代谢综合征临床研究 被引量:8
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作者 杨宇峰 滕飞 石岩 《中华中医药学刊》 CAS 2012年第11期2406-2408,共3页
目的:观察中药益糖康干预并有并有糖调节受损的代谢综合征的临床疗效。方法:通过对患者空腹血糖(fasting plasma glucose,FPG)、餐后2h血糖(2 hours plasma glucose;postprandial blood glucose;2hPG,PBG)、糖化血红蛋白(HbAlc)、体重(b... 目的:观察中药益糖康干预并有并有糖调节受损的代谢综合征的临床疗效。方法:通过对患者空腹血糖(fasting plasma glucose,FPG)、餐后2h血糖(2 hours plasma glucose;postprandial blood glucose;2hPG,PBG)、糖化血红蛋白(HbAlc)、体重(body weight,BW)、总胆固醇(total cholesterol,TC)、甘油三酯(triglyceride,TG)、高密度脂蛋白(high density lipoprotein,HDL-C)、低密度脂蛋白(low density lipoprotein,LDL-C)等主要指标进行分析。结果:①中药益糖康组FPG降低,与西药组(二甲双胍)相比,具有显著差异(P<0.05)。②中药益糖康组HbAlc、2hPG降低,与西药组(二甲双胍)相比,无显著差异(P>0.05)。③1年后中药益糖康组患者HbAlc较基线下降(P<0.005)。④1年后中药益糖康组患者的血脂谱与基线相比:TG下降16%(P<0.005),TC下降10%(P<0.005),LDL-C下降8%(P<0.0001),而HDL-C升高24%(P<0.0001)。⑤患者FPG每下降0.8mmol/L,BW平均下降0.9kg,与西药组(二甲双胍)相比,具有显著差异(P<0.005)。结论:中药益糖康可降糖、减轻体重,改善血脂谱,具有潜在的心血管收益。 展开更多
关键词 益糖康 糖调节受损(impaired GLUCOSE regulation IGR) 代谢综合征(metabolic syndrome MS) 临床研
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IcarisideⅡ alleviates oxygen-glucose deprivation and reoxygenation-induced PC12 celloxidative injury by activating Nrf2 / SIRT3signaling pathway 被引量:15
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作者 FENG Lin-ying GAO Jian-mei +2 位作者 LIU Yuan-gui SHI Jing-shan GONG Qi-hai 《中国药理学与毒理学杂志》 CAS CSCD 北大核心 2018年第9期667-668,共2页
OBJECTIVE To investigate icariside(ICS)Ⅱ protects against PC12 cel damage induced by oxygen-glucose deprivation and reoxygenation and explore its mechanism.METHODS The oxidative stress injury model was induced by oxy... OBJECTIVE To investigate icariside(ICS)Ⅱ protects against PC12 cel damage induced by oxygen-glucose deprivation and reoxygenation and explore its mechanism.METHODS The oxidative stress injury model was induced by oxygen-glucose deprivation/reoxygenation(OGD/R) 2 h/24 h in PC12 cells.N-acetyl-lcysteine(NAC),a classical anti-oxidant,was used as positive control.Pharmacodynamic experimental study groups as follows:control,control+ICS Ⅱ50 μmol·L^(-1),OGD/R,OGD/R+ICSⅡ 12.5 μmol·L^(-1),OGD/R + ICS Ⅱ 25 μmol·L^(-1),OGD/R + ICS Ⅱ50 μmol·L^(-1),and OGD/R+NAC 100 μmol·L^(-1) groups.Cell viability and lactate dehydrogenase(LDH) leakage rate were measured by MTT assay and LDH ELISA kit,respectively.Moreover,reactive oxygen species(ROS) ELISA kit was used for detection of intracellular ROS generation,Mito-SOX fluorescence staining was used for detecting production of ROS in mitochondria and mitochondrial membrane potential(MMP)was detected by rhodamine 123 dye.In addition,PC12 cells apoptosis was detected by one-step TUNEL assay.Furthermore,the expressions of nuclear factor erythroid 2-related factors(Nrf2),Keap1,HO^(-1),NQO^(-1),silent information regulator 3(SIRT3),IDH2,Bax,Bcl-2 and caspase 3 were detected by Western blotting analysis.RESULTS The results of MTT and LDH assay showed that OGD/R reduced the cell viability and improved LDH release compared with the control or ICSⅡ 50 μmol·L^(-1) alone(P<0.01).Meanwhile,OGD/R not only increased intracellular and mitochondrial ROS generation,but also elevated the fluorescence intensity of TUNEL staining,at the same time,the MMP was declined when challenged by OGD/R.Furthermore,the Western blotting results showed that OGD/R induced the increase in the expression of cytoplasm-Nrf2,Keap1,Bax and cleaved-caspase 3 level,while the decrease in the expression of nucleus-Nrf2,HO^(-1),NQO^(-1),SIRT3,IDH2 and Bcl-2(P<0.05).However,ICS Ⅱ significantly increased the viability of PC12 cells and reduced LDH leakage(P<0.01).Notably,ICS Ⅱ also suppressed ROS generation both in the intracellular and mitochondria,as well as restored MMP.It was also worthy to note that ICS Ⅱ decreased the expressions of cytoplasmNrf2,Keap1,Bax and the level of cleaved-caspase3,whereas,it increased the expressions of nucleus-Nrf2,HO^(-1),NQO^(-1),SIRT3,IDH2 and Bcl-2(P<0.05).CONCLUSION ICSⅡ reduced OGD/Rinduced oxidative damage in PC12 cells under the laboratory conditions,and its underlying mechanism may be related to the regulation of Nrf2/SIRT3 signaling pathway. 展开更多
关键词 icariside oxygen-glucose DEPRIVATION REOXYGENATION oxidative injury apoptosis nuclear factor ERYTHROID 2-related factors SILENT information regulator 3
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