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Electronic structure regulation on layered double hydroxides for oxygen evolution reaction 被引量:5
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作者 Liangliang Huang Yuqin Zou +1 位作者 Dawei Chen Shuangyin Wang 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2019年第12期1822-1840,共19页
Oxygen evolution reactions(OERs)as core components of energy conversion and storage technology systems,such as water splitting and rechargeable metal–air batteries,have attracted considerable attention in recent year... Oxygen evolution reactions(OERs)as core components of energy conversion and storage technology systems,such as water splitting and rechargeable metal–air batteries,have attracted considerable attention in recent years.Transition metal compounds,particularly layered double hydroxides(LDHs),are considered as the most promising electrocatalysts owing to their unique two-dimensional layer structures and tunable components.However,heir poor intrinsic electrical conductivities and the limited number of active sites hinder their performances.The regulation of the electronic structure is an effective approach to improve the OER activity of LDHs,including cationic and anionic regulation,defect engineering,regulation of intercalated anions,and surface modifications.In this review,we summarize recent advances in the regulation of the electronic structures of LDHs used as electrocatalysts in OERs.In addition,we discuss the effects of each regulation type on OER activities.This review is expected to shed light on the development and design of effective OER electrocatalysts by summarizing various electronic structure regulation pathways and the effects on their catalytic performances. 展开更多
关键词 Oxygen evolution reactions Layered double hydroxide Cationic/Anionic regulation Defect engineering ELECTROCATALYST ELECTRON DOPING
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Codon evolution in double-stranded organelle DNA: strong regulation of homonucleotides and their analog alternations 被引量:2
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作者 Kenji Sorimachi 《Natural Science》 2010年第8期846-854,共9页
In our previous study, complete single DNA strands which were obtained from nuclei, chloroplasts and plant mitochondria obeyed Chargaff’s second parity rule, although those which were obtained from animal mitochondri... In our previous study, complete single DNA strands which were obtained from nuclei, chloroplasts and plant mitochondria obeyed Chargaff’s second parity rule, although those which were obtained from animal mitochondria deviated from the rule. On the other hand, plant mitochondria obeyed another different rule after their classification. Complete single DNA strand sequences obtained from chloroplasts, plant mitochondria, and animal mitochondria, were divided into the coding and non-coding regions. The non-coding region, which was the complementary coding region on the reverse strand, was incorporated as a coding region in the forward strand. When the nucleotide contents of the coding region or non-coding regions were plotted against the composition of the four nucleotides in the complete single DNA strand, it was determined that chloroplast and plant mitochondrial DNA obeyed Chargaff’s second parity rule in both the coding and non-coding regions. However, animal mitochondrial DNA deviated from this rule. In chloroplast and plant mitochondrial DNA, which obey Chargaff’s second parity rule, the lines of regression for G (purine) and C (pyrimidine) intersected with regression lines for A (purine) and T (pyrimidines), respectively, at around 0.250 in all cases. On the other hand, in animal mitochondrial DNA, which deviates from Chargaff’s second parity rule, only regression lines due to the content of homonucleotides or their analogs in the coding or non-coding region against those in the complete single DNA strand intersected at around 0.250 at the horizontal axis. Conversely, the intersection of the two lines of regression (G and A or C and T) against the contents of heteronucleotides or their analogs shifted from 0.25 in both coding and non-coding regions. Nucleotide alternations in chloroplasts and plant mitochondria are strictly regulated, not only by the proportion of homonucleotides and their analogs, but also by the heteronucleotides and their analogs. They are strictly regulated in animal mitochondria only by the content of homonucleotides and their analogs. 展开更多
关键词 CODON EVOLUTION in double-STRANDED organelle DNA: STRONG regulATION of homonucleotides and their ANALOG alternations
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Long-lasting growth regulation on cotton using mepiquat chloride adsorbed layered double hydroxide 被引量:1
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作者 Chong Wang Changcheng An +5 位作者 Ningjun Li Changjiao Sun Yue Shen Shenshan Zhan Xingye Li Yan Wang 《Advanced Agrochem》 2024年第1期57-63,共7页
Mepiquat chloride(1,1-dimethyl piperidinium chloride,DPC)is a representative plant growth regulator which can regulate the source-sink relationship for yield increase and shape ideal plant type for mechanical cultivat... Mepiquat chloride(1,1-dimethyl piperidinium chloride,DPC)is a representative plant growth regulator which can regulate the source-sink relationship for yield increase and shape ideal plant type for mechanical cultivation.Here we show a DPC adsorbed layered double hydroxide(DPC-LDH)architecture with enhanced controlled release property and soil distribution.By drip irrigation on cotton,it makes total dosage of DPC reduced from 270 to 90 g/ha,while the frequency decreased from 5 to 2 times.The unique supramolecular interaction is confirmed as the basis of controlled release behavior.Moreover,except for the physical resistance to the sedimentation brought by the lamellar LDH,the enhanced electrostatic interaction makes DPC-LDH the dominant distribution in soil.It improves the efficiency of DPC molecules absorbed by cotton plants and greatly saves the inputs in labor and chemicals.This method is expected to achieve the yield increase and agricultural sustainability by energy saving and emission reduction. 展开更多
关键词 Layered double hydroxide Plant growth regulation Controlled release CO2 emission reduction Nano-pesticide
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Application of Single Neuron Adaptive PID Regulators with Auto-tuning Gain in Industrial Parameter(Pressure)Closed-loop Process Control Systems 被引量:1
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作者 Shaoyuan Sun Huade Li +1 位作者 Bin Qian Jianping Wei(Information Engineering School, University of Science and Technology Beijing, Beijing 100083, China) 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 1999年第2期152-153,共2页
A type of single neuron adaptive PID regulator with auto-tuning gain is proposed and applied to the work control of fans, waterpumps and air-pressers etc. in Handan Iron & Steel Compel China. The robusthess of ind... A type of single neuron adaptive PID regulator with auto-tuning gain is proposed and applied to the work control of fans, waterpumps and air-pressers etc. in Handan Iron & Steel Compel China. The robusthess of induStrial parameter closed-loop process controlsystems is improved, and the work quality of the systems bettered. 展开更多
关键词 single neuron GAIN adaptiVe PID regulator pressure closed-loop control
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Study on a Novel Digital Electro-Hydraulic Pressure Valve with a Capillary Damping Tube Regulating Pressure
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作者 许耀铭 宋文健 李宝仁 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1994年第1期26-29,共4页
A digital electro-hydraulic 4-port differential pressure control valve with a novel principle and structure is presented. The valve is designed by applying the regulating pressure technique of a capillary damping tube... A digital electro-hydraulic 4-port differential pressure control valve with a novel principle and structure is presented. The valve is designed by applying the regulating pressure technique of a capillary damping tube and also making full use of double freedom of the spool motion. Thevalve can implement digitizing interface easily. The theoretical analysis and experimental resultsshow that the valve is not only very simple in structure and convenient in use, but also has manygood properties, such as fast response, no-null-shift, etc. 展开更多
关键词 ss: PRESSURE regulation CAPILLARY DAMPING TUBE double freedom of the SPOOL motion electro-hydrolic PRESSURE VALVE digitization
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液晶填充一维阶梯型Double-period结构局域模的调控特性
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作者 黄志红 《南昌大学学报(理科版)》 CAS 北大核心 2016年第6期536-541,共6页
利用传输矩阵法研究了向列相液晶填充一维阶梯型Double-period第4代准周期结构局域模的电场方向、外界温度调控特性。通过改变电场方向和外界温度,研究该结构透射谱的调控特性。结果表明:温度一定时,液晶的有效折射率都随着夹角θ的增... 利用传输矩阵法研究了向列相液晶填充一维阶梯型Double-period第4代准周期结构局域模的电场方向、外界温度调控特性。通过改变电场方向和外界温度,研究该结构透射谱的调控特性。结果表明:温度一定时,液晶的有效折射率都随着夹角θ的增大而逐渐减小,局域模波长随夹角θ的增大而发生蓝移;当夹角θ接近54°时,向列相液晶的有效折射率与温度呈现近正比线性关系;夹角θ小于54°时,向列相液晶的有效折射率随温度升高而逐渐减小,局域模波长随外界温度(300~378.15K)的升高而发生蓝移;夹角θ大于54°时,随温度升高,向列相液晶的有效折射率先减小后增大,局域模波长先发生蓝移再发生红移。无论是外界温度升高还是电场方向夹角的增大,局域模的调控量始终是减小的,且局域模的调控量与液晶有效折射率差值成正比线性关系。 展开更多
关键词 阶梯型double-period结构 局域模 传输矩阵法 调控量 折射率差值
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High Efficiency Double–Fed Induction Generator Applied to Wind Power Generator Technical Analyses
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作者 Deng-Chern Sue 《Energy and Power Engineering》 2011年第3期253-261,共9页
High efficiency Double-Fed Induction Generator applies new power electronic technology, and utilizes vector control to fix the magnetic direction of the stator to the vertical axis. Adjusting the input current of roto... High efficiency Double-Fed Induction Generator applies new power electronic technology, and utilizes vector control to fix the magnetic direction of the stator to the vertical axis. Adjusting the input current of rotor via an inverter can separately control the cross axis and vertical axis current of real power and reactive power of a generator. Traditionally, rotating speed affects frequency and the output is unstable. This study concentrates on high efficiency Double-Fed Induction Generators and Traditional Generators from mathematic model to derive and control the characteristics simulation and comparison than get an output of high efficiency Double-Fed Industrial Generators. This study utilizes the simulation software MATLAB/Simulink to simulate the response characteristics of vector control of a Double-Fed Industrial Generator. The operating and control functions are better than those of a traditional generator. 展开更多
关键词 double-Fed Induction Generator CUT-IN Speed PUSHOVER TORQUE STALL regulATOR PITCH regulATOR Inverter
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Development and Analysis of the Magnetic Circuit on Double-Radial Permanent Magnet and Salient-Pole Electromagnetic Hybrid Excitation Generator for Vehicles
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作者 Xueyi Zhang Qinjun Du +2 位作者 Jinbin Xu Yuzhen Zhao Shilun Ma 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2019年第2期100-112,共13页
With the improvement of vehicles electrical equipment, the existing silicon rectification generator and permanent magnet generator cannot meet the requirement of the electric power consumption of the modern vehicles e... With the improvement of vehicles electrical equipment, the existing silicon rectification generator and permanent magnet generator cannot meet the requirement of the electric power consumption of the modern vehicles electrical equipment. It is di cult to adjust the air gap magnetic field of the permanent magnet generator. Consequently, the output voltage is not stable. The silicon rectifying generator has the problems of low e ciency and high failure rate.In order to solve these problems, a new type of hybrid excitation generator is developed in this paper. The developed hybrid excitation generator has a double-radial permanent magnet, a salient-pole electromagnetic combined rotor,and a fractional slot winding stator, where each rotor pole corresponds to 4.5 stator teeth. The equivalent magnetic circuit diagram of permanent magnet rotor and magnetic rotor is established. Magnetic field finite element analysis(FEA) software is used to conduct the modeling and simulation analysis on double-radial permanent magnet magnetic field, salient-pole electro-magnetic magnetic field and hybrid magnetic field. The magnetic flux density mold value diagram and vector diagram are obtained. The diagrams are used to verify the feasibility of this design. The designed electromagnetic coupling regulator controller can ensure the stable voltage export by changing the magnitude and direction of the excitation current to adjust the size of the air gap magnetic field. Therefore, the problem of output voltage instability in the wide speed range and wide load range of the hybrid excitation generator is solved. 展开更多
关键词 Vehicle Hybrid excitation GENERATOR double-radial permanent magnet Salient-pole ELECTROMAGNETIC ELECTROMAGNETIC coupling regulATOR controller
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碳排放权交易政策对企业绿色转型的影响研究——基于控排企业名单视角
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作者 刘婧 曹梦娇 《山东工商学院学报》 2026年第1期27-44,共18页
基于2010—2020年沪深A股上市公司的数据,以碳排放权交易为准自然实验,用控排企业名单视角构建多期DID模型,研究碳交易市场对企业绿色转型的影响以及作用机制。研究发现,碳排放权交易显著促进了企业的绿色转型水平,且碳排放权交易政策... 基于2010—2020年沪深A股上市公司的数据,以碳排放权交易为准自然实验,用控排企业名单视角构建多期DID模型,研究碳交易市场对企业绿色转型的影响以及作用机制。研究发现,碳排放权交易显著促进了企业的绿色转型水平,且碳排放权交易政策可以通过缓解融资约束以及加强企业内外管理的方式提高企业绿色转型水平。 展开更多
关键词 碳排放权交易 企业绿色转型 双重差分模型 环境规制
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国家生态文明建设示范区对城市韧性的影响研究
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作者 蒋锋 龙珂良 《统计与信息论坛》 北大核心 2026年第1期61-76,共16页
作为衡量城市系统应对外部扰动时所展现的抵抗力、恢复力及适应能力的综合性指标,城市韧性已逐渐成为推动可持续发展的核心议题。国家生态文明建设示范区政策旨在提升城市的生态文明建设水平并实现可持续发展,同时在增强城市韧性方面也... 作为衡量城市系统应对外部扰动时所展现的抵抗力、恢复力及适应能力的综合性指标,城市韧性已逐渐成为推动可持续发展的核心议题。国家生态文明建设示范区政策旨在提升城市的生态文明建设水平并实现可持续发展,同时在增强城市韧性方面也发挥着积极作用。通过构建熵权深度神经网络模型用于测度城市韧性指数,并将国家生态文明建设示范区政策作为准自然实验,利用多时点双重差分法分析国家生态文明建设示范区对城市韧性的具体影响。研究结果表明:第一,国家生态文明建设示范区政策可以显著提升城市韧性,这一结论通过了多种稳健性检验;第二,国家生态文明建设示范区政策可以通过绿色技术创新、环境规制两种渠道提升城市韧性;第三,国家生态文明建设示范区政策对资源型城市、非资源型城市、东部城市、胡焕庸线东南侧城市、陡坡及以上城市的城市韧性有显著提升作用;第四,碳排放强度在国家生态文明建设示范区政策与城市韧性之间起到负向的调节作用。基于上述结论,相关部门应坚持推进示范区建设工作,科学利用政策传导渠道,充分发挥政策在提升城市韧性方面的引导作用,推动形成生态文明共建共治共享的新格局。 展开更多
关键词 国家生态文明建设示范区 城市韧性 熵权深度神经网络模型 多时点双重差分法 双重机器学习 绿色技术创新 环境规制 碳排放强度
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双星并联光纤激光网络通信带宽自调节研究
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作者 王莉 李丹 沈玲玲 《激光杂志》 北大核心 2026年第1期143-148,共6页
为了有效优化双星并联光纤激光网络通信性能,提出一种双星并联光纤激光网络通信带宽自调节方法。将双星并联光纤激光网络通信带宽利用率最大化和通信节点的最坏延迟总和最小作为目标函数,以通信时延和误码率等作为约束条件,构建双星并... 为了有效优化双星并联光纤激光网络通信性能,提出一种双星并联光纤激光网络通信带宽自调节方法。将双星并联光纤激光网络通信带宽利用率最大化和通信节点的最坏延迟总和最小作为目标函数,以通信时延和误码率等作为约束条件,构建双星并联光纤激光网络通信带宽自调节模型。对粒子群方法展开改进,应用改进后的PSO方法对模型求解,确定通信带宽最优自调节方案。实验结果表明,所提方法在单次迭代时间上仅需5.1 ms,内存占用为35 MB,有效降低平均队列长度,提升上行信道利用率和带宽利用率,有效确保双星并联光纤激光网络的稳定性和可靠性。 展开更多
关键词 双星并联 光纤激光网络 通信带宽 自调节
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深水双层管双梯度钻井流量调节与井筒压力控制研究
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作者 张政 许智博 +2 位作者 王国荣 钟林 唐洋 《中国海上油气》 北大核心 2026年第1期195-208,共14页
深水区地层普遍存在窄安全密度窗口的特性,显著增加了钻井作业中井下压力控制的难度,严重制约了深水油气资源的高效开发。针对该技术瓶颈,本文基于理论分析与数值模拟相结合的方法,系统探究了深水双层管双梯度钻井技术体系下井底压力动... 深水区地层普遍存在窄安全密度窗口的特性,显著增加了钻井作业中井下压力控制的难度,严重制约了深水油气资源的高效开发。针对该技术瓶颈,本文基于理论分析与数值模拟相结合的方法,系统探究了深水双层管双梯度钻井技术体系下井底压力动态调控机制。建立了钻井水力学参数与井底压力的耦合计算模型,分析了钻进过程中井底压力的变化规律,揭示了钻井泵排量、举升泵扬程和井底压力三者之间的关系;通过海上试验验证调节举升泵流量可精准控制钻井液当量密度,实现井底压力的主动调控。本研究通过调节举升泵流量调控井底压力,基于环空隔离液液位变化动态调整扬程,实现钻井液当量密度精准控制,以期保障深水钻井安全并支撑油气高效开发。 展开更多
关键词 深水 双梯度钻井 窄密度窗口 双层管 反循环 压力调控
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纵向磁场调控双丝单弧MAG焊电弧行为及焊缝成形分析
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作者 张乾 张鸿昌 +2 位作者 李一楠 陈铭浩 张洪涛 《焊接学报》 北大核心 2026年第1期79-86,共8页
磁控双丝单弧MAG焊作为一种新型的高效焊接工艺方法,由于其电弧可控性较差,在焊接过程中易受外界干扰.文中采用自主设计的励磁装置对双丝单电弧MAG焊施加纵向磁场进行调控.其中,基于Maxwell有限元仿真软件定量表征了励磁强度随励磁电流... 磁控双丝单弧MAG焊作为一种新型的高效焊接工艺方法,由于其电弧可控性较差,在焊接过程中易受外界干扰.文中采用自主设计的励磁装置对双丝单电弧MAG焊施加纵向磁场进行调控.其中,基于Maxwell有限元仿真软件定量表征了励磁强度随励磁电流的变化规律,获得不同空间位置下的磁感线分布及磁感应强度分布.通过焊接工艺试验,研究了不同励磁参数下的焊接电弧行为变化规律,分析了外加纵向磁场对焊缝成形及焊缝截面几何特征的影响.结果表明,施加的外部磁场在一定范围内能够有效提高双丝电弧挺度及焊接过程的稳定性,从而大幅度改善焊缝成形质量.外加纵向磁场的变化主要影响焊缝熔深和熔宽,且两者总体呈现相反的变化趋势.当励磁电流为1.5 A,励磁频率为80 Hz时,焊缝成形质量最好. 展开更多
关键词 磁场调控 电弧形态 双丝单弧 焊缝成形 励磁电流
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低碳城市试点对企业绿色创新的影响研究——基于双重机器学习的实证评估
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作者 佟璐 《生态经济》 北大核心 2026年第2期184-193,共10页
论文采用双重机器学习方法,基于2010—2023年中国上市公司样本,将低碳城市试点政策视为准自然实验,系统考察其对企业绿色技术创新的因果效应。研究结果表明:低碳城市建设显著提升了试点城市企业的绿色创新能力,该结论在经过一系列系统... 论文采用双重机器学习方法,基于2010—2023年中国上市公司样本,将低碳城市试点政策视为准自然实验,系统考察其对企业绿色技术创新的因果效应。研究结果表明:低碳城市建设显著提升了试点城市企业的绿色创新能力,该结论在经过一系列系统性的稳健性检验后依然成立。机制分析表明,低碳城市试点政策通过增加企业的研发投入、提升政府环境规制的强度以及缓解企业的融资约束三个途径促进了企业绿色创新。异质性分析发现,政策的绿色创新效应在市场化程度较高的非公有制企业、规模较大的企业以及重污染行业中的作用更为显著,揭示了制度环境与主体特征协同优化的内在逻辑。研究成果为完善环境政策的微观传导机制提供了理论依据,同时为构建差异化低碳治理框架、加速经济绿色转型提供了决策启示。 展开更多
关键词 低碳城市 绿色创新 双重机器学习 研发投入 环境规制
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Neuromimetic circuits enabled by dynamic regulation of the electrical double layer
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作者 Xiang Li Tinghai Cheng +1 位作者 Zhong Lin Wang Di Wei 《npj Flexible Electronics》 2025年第1期1126-1132,共7页
Iontronics presents a transformative paradigm for energy and information processing via ions as active charge carriers.Here,triboiontronics is introduced,a novel strategy leveraging contact electrification to achieve ... Iontronics presents a transformative paradigm for energy and information processing via ions as active charge carriers.Here,triboiontronics is introduced,a novel strategy leveraging contact electrification to achieve dynamic regulation of electrical double layers.Inspired by signaling mechanisms of biological neural systems,triboiontronics enables enhanced ionic-electronic coupling without external power input,offering a material-independent and self-powered pathway for programmable interfacial behavior,underscoring its promise for post-Moore,energy-autonomous information technologies. 展开更多
关键词 neuromimetic biological neural systemstriboiontronics signaling mechanisms programmable interfacial behaviorunder dynamic regulation electrical double layersinspired contact electrification tribiontronics active charge carriersheretriboiontronics
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An Implanted Closed-loop Chip System for Heart Rate Control:System Design and Effects in Conscious Rats 被引量:3
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作者 Yuxuan Zhou Yuan Yuan +4 位作者 Juan Gao Ling Yang Feng Zhang Guoqing Zhu Xingya Gao 《The Journal of Biomedical Research》 CAS 2010年第2期107-114,共8页
Objective: To evaluate the efficiency of an implanted chip system for the control of heart rate (HR). Methods: The HR was recorded in six conscious Sprague-Dawley (SD) rats. An implanted chip system was designed... Objective: To evaluate the efficiency of an implanted chip system for the control of heart rate (HR). Methods: The HR was recorded in six conscious Sprague-Dawley (SD) rats. An implanted chip system was designed to regulate the HR by stimulating the right cervical vagus nerve according to the feedback of real time HR. Each rat was subjected to 30-min regulation and 30-min recovery. The change of HR during the regulation period was compared with the control. The ECG was recorded during the experiment for 24 h. Results: The ECG signals were successfully recorded during the experiment. The HR was significantly decreased during the period of regulation compared with control (-79.3 ± 34.5, P 〈 0.01, n = 6) and then recovered to normal after regulation. Conclusion: The described implanted chip system can regulate the HR to a designated set point. 展开更多
关键词 closed-loop regulation implanted chip system set point heart rate vagus nerve stimulation Remote-controlled animal
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农业环境规制对城乡融合发展的影响——基于国家农业绿色发展先行区的准自然实验 被引量:3
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作者 伍国勇 陈高哲 程建伟 《中国人口·资源与环境》 北大核心 2025年第2期171-184,共14页
作为农业发展制度体系的重要构件,农业环境规制能否促进城乡融合发展对中国式现代化建设至关重要。该研究以第一批国家农业绿色发展先行区的设立为准自然实验,基于2011—2022年中国280个地级市及以上城市面板数据,从经济、社会、生态3... 作为农业发展制度体系的重要构件,农业环境规制能否促进城乡融合发展对中国式现代化建设至关重要。该研究以第一批国家农业绿色发展先行区的设立为准自然实验,基于2011—2022年中国280个地级市及以上城市面板数据,从经济、社会、生态3个维度出发构建城乡融合发展评价指标体系,采用双重机器学习模型实证检验农业环境规制对城乡融合发展的作用效果和内在机制,并探讨了其异质性和多维度影响。研究发现:①农业环境规制能够有效促进城乡融合发展,这一结果在通过一系列检验后依然稳健。②机制检验表明,农业环境规制主要通过推动农业现代化和公共资本要素流动促进城乡融合发展,但对农业绿色转型并未产生显著影响。③异质性分析表明,农业环境规制对资源型城市的城乡融合发展效应存在一定程度的“资源诅咒”困境;中、西部地区由于经济、社会条件相比东部地区较为落后,难以完全发挥农业环境规制的政策效应;财政自主权越大越有助于增强农业环境规制对城乡融合发展的促进作用。④分维度来看,农业环境规制显著促进了城乡经济融合和城乡社会融合,但对城乡生态融合并未产生显著影响,表现出“绿色悖论”现象。基于上述研究结论,提出建议:持续推进国家农业绿色发展先行区建设、完善政府监管和市场激励机制、关注地区异质性精准施策。 展开更多
关键词 农业 环境规制 城乡融合 国家农业绿色发展先行区 双重机器学习
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市场型环境规制对碳排放强度的影响效应和机制研究——基于碳交易试点政策的经验证据 被引量:1
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作者 哈梅芳 黄奕晗 《生态经济》 北大核心 2025年第2期38-44,共7页
作为市场型环境规制手段的碳排放权交易是助力实现“双碳”目标的重要政策。基于2009—2019年中国省级面板数据,运用双重差分法,探究碳交易试点政策的实施对碳强度的影响效应和影响机制。研究发现:碳交易试点政策有效降低了试点地区的... 作为市场型环境规制手段的碳排放权交易是助力实现“双碳”目标的重要政策。基于2009—2019年中国省级面板数据,运用双重差分法,探究碳交易试点政策的实施对碳强度的影响效应和影响机制。研究发现:碳交易试点政策有效降低了试点地区的碳排放强度,发挥了市场型环境规制的积极作用,而且碳交易机制通过影响能源消费量这一渠道遏制了碳排放强度的增长。通过调节效应模型发现,地区产业结构负向调节碳交易试点政策的降碳效应,而政府规模则正向调节碳交易试点政策的降碳效应。以上结论为进一步推动全国性碳交易市场稳健发展、发挥市场型环境规制的积极作用以及推进“双碳”目标实现提供了重要的经验证据。 展开更多
关键词 市场型环境规制 碳交易试点政策 碳排放强度 双重差分法 机制
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生物炭基层状双金属氢氧化物复合材料去除环境污染物的研究进展
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作者 王博 李婧雯 +2 位作者 费超 李辰 范志平 《精细化工》 北大核心 2025年第6期1240-1249,1365,共11页
层状双金属氢氧化物(LDHs)是一类具有层状结构的无机功能材料,将LDHs负载到生物炭(BC)上,形成的生物炭基层状双金属氢氧化物(BC/LDHs)复合材料结合了BC和LDHs的优点,在去除环境污染物方面展现出巨大的潜力。该文全面探讨了BC/LDHs复合... 层状双金属氢氧化物(LDHs)是一类具有层状结构的无机功能材料,将LDHs负载到生物炭(BC)上,形成的生物炭基层状双金属氢氧化物(BC/LDHs)复合材料结合了BC和LDHs的优点,在去除环境污染物方面展现出巨大的潜力。该文全面探讨了BC/LDHs复合材料在环境污染物去除领域的研究进展。讨论了BC/LDHs复合材料的制备方法,包括共沉淀法、共热解法和水热合成法;介绍了其性能调控策略,如异质原子掺杂、化学浸渍和赋磁强化等;总结了BC/LDHs复合材料在去除染料、重金属、营养盐和抗生素等方面的应用效果,分析归纳了其对环境污染物去除的关键机制;最后,指出了BC/LDHs复合材料在环境应用中存在的局限性,如对特定污染物的去除率、在复杂环境条件下的适应能力以及材料的长期稳定性等问题,并提出了相应的解决策略。 展开更多
关键词 生物炭 层状双金属氢氧化物 环境污染物 去除 性能调控
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中性粒细胞胞外陷阱在炎症性疾病中的“双刃剑”效应
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作者 高爽 王天鸽 +1 位作者 林树梅 赵冬冬 《黑龙江畜牧兽医》 北大核心 2025年第5期59-62,共4页
炎症是机体抵抗感染或损伤的一种免疫反应。适度的炎症反应(持续时间短暂)通常能产生积极效应;相反,若炎症反应过度且迁延不愈,则可能诱发组织损害,从而导致如急性肺损伤、急性呼吸窘迫综合征、炎症性肠道疾病及类风湿关节炎等多种炎症... 炎症是机体抵抗感染或损伤的一种免疫反应。适度的炎症反应(持续时间短暂)通常能产生积极效应;相反,若炎症反应过度且迁延不愈,则可能诱发组织损害,从而导致如急性肺损伤、急性呼吸窘迫综合征、炎症性肠道疾病及类风湿关节炎等多种炎症相关疾病的发生。中性粒细胞胞外陷阱(neutrophil extracellular traps,NETs)是中性粒细胞在活化后释放到细胞外的由染色质和多种蛋白成分组成的网状结构。近年的研究表明,NETs在炎症性疾病中起着“双刃剑”的作用,对机体保护的同时其组蛋白成分也可导致细胞、组织损伤。本文综述了NETs的形成、功能及意义,探讨了其在炎症性疾病中所展现出的“双刃剑”效应,从而深化了对NETs在炎症性疾病发生与进展中具体作用的认知。 展开更多
关键词 中性粒细胞胞外陷阱 炎症性疾病 “双刃剑”效应 调控 功能
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