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Antifertility effects of EP-1 (quinestrol and levonorgestrel) on Pacific rats (Rattus exulans)

Integrative Zoology 2024年第1期19卷 127-142页

作者： Jing liu Feiyun TU Ming liu jichao WANG Zhibin ZHANG Ministry of Education Key Laboratory for Ecology of Tropical Islands Key Laboratory of Tropical Animal and Plant Ecology of Hainan ProvinceCollege of Life SciencesHainan Normal UniversityHaikouHainanChina Secretariat Office International Society of Zoological Science and Society and Journal OfficeInstitute of ZoologyChinese Academy of SciencesBeijingChina State Key Laboratory of Integrated Management of Pest Insects and Rodents Institute of ZoologyChinese Academy of SciencesBeijingChina CAS Center for Excellence in Biotic Interactions University of Chinese Academy of SciencesBeijingChina

Pest rodents pose a serious threat to island biodiversity.Fertility control could be an alternative approach to control the impact of rodents on these islands.In this study,we examined the antifertility effects of EP-1 baits containing quinestrol(E)and levonorgestrel(P)using a dose of 50 ppm E and P at three different ratios(E:P ratio=1:2,1:1,and 2:1)on Pacific rats(Rattus exulans)in the Xisha Islands,Hainan,China.Compared to the control group,all animals in EP-1 treatment groups showed significantly decreased food intake and body weight.In treated males,there were obvious abnormalities in testis structure and a significant decrease of relative seminal vesicle weight,but no significant effect on relative uterine and ovarian weights(g kg-1 body weight),or ovarian structure in females.Adding 8%sucrose to the original 50-ppm baits(E:P ratio=1:1)significantly increased bait palatability for males and females.This dose induced uterine edema and abnormalities of ovarian structure in females but had no significant negative effect on the relative testis,epididymis,and seminal vesicle weights(g kg-1 body weight)or sperm density in males.In summary,50-ppm EP-1(1:1)baits have the potential to disrupt the fertility of females,and 8%sucrose addition to the EP-1 baits(E:P ratio=1:1)could improve bait palatability.This dose disrupted the testis structure in males.Future studies are needed to improve bait acceptance and assess the antifertility effects of EP-1(1:1)on Pacific rats in captive breeding trials and underfield conditions.

关键词： EP-1 fertility control island biodiversity conservation levonorgestrel quinestrol Rattus exulans

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Design and performance investigation of modified dual reflector parabolic trough collector with double planar mirrors

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Science China(Technological Sciences) 2024年第3期67卷 902-918页

作者： LI Peijing liu TaiXiu QIN YuanLong LI jichao liu QiBin School of Energy Powerand Mechanical EngineeringNorth China Electric Power University Beijing 226China Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Department of Thermal Science and Energy Engineering University of Science and Technology of ChinaHefei 230027China

In a typical parabolic trough collector(PTC), sunlight is concentrated at the bottom of the absorber tube. This concentrated solar flux leads to uneven heat distribution, resulting in high local temperatures and significant thermal stress on the absorber tube.These limitations have restricted the application of PTCs in solar thermochemistry and other fields and have impacted their safe operation. In this study, a new PTC with dual planar mirrors(DPMS) is proposed to homogenize the circumferential solar flux distribution of the absorber tube. A design method and single-objective optimization of the new PTC with a DPMS are proposed,and an uncertainty analysis of the operational and structural parameters is performed. A coupled light-heat-structure numerical model was developed to study the heat transfer performance and structural mechanical properties. The thermodynamic properties of the PTC with DPMS under different boundary conditions were analyzed. The results show that the circumferential temperature difference of the new PTC is within 2.6 K, and the circumferential thermal deformation is within 0.9 mm under typical working conditions(the inlet velocity of the heat transfer fluid is 3 m/s, inlet temperature is 573.15 K, and the direct normal irradiance is 1000 W/m^(2)). Compared with conventional PTCs, the circumferential temperature difference is reduced by 74%–90%, and the maximum thermal deformation along the y-axis is reduced by more than 95% under all working conditions(1–5 m/s, 373.5–675.15 K, 200–1000 W/m^(2)). The new PTC maintains the uniformity of the circumferential solar flux distribution for different operating parameters(sun incident angle of 0°–3°) and installation errors(±3 mm), is suitable for solar energy applications in various fields, and has the potential for large-scale applications.

关键词： solar thermal energy parabolic trough collector secondary reflector solar flux distribution optical optimization

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High-efficiency Multiplexed Buck-type PFC Converter

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CSEE Journal of Power and Energy Systems 2024年第3期10卷 1053-1063页

作者： Lunquan Li Qianhong Chen jichao Huang Bin liu School of Automation Nanjing University of Aeronautics and AstronauticsNanjing 211106China Gaoyi Zhineng Electric Ltd. Shenzhen 518101China School of Information Engineering Nanchang Hang Kong UniversityNanchang 330063China IEEE CSEE

This paper proposes a high-efficiency PFC rectifier based on multiplexing the switches.Compared with a traditional six-switch PFC rectifier,the proposed rectifier extends the switches’active angle by making use of three bridge rectifiers.As a result,lower conduction resistance can be realized for switches.Consequently,system efficiency can be improved.Compared with a traditional six-switch PFC rectifier with doubled switches,the proposed rectifier can achieve almost the same efficiency improvement while no additional switches are needed.Since continuous inductor current is chopped and resulting current pulses cannot be injected into the grid directly,input filter design and resonance damping are discussed for the proposed rectifier.The controller design of the rectifier is analyzed.The inductor current reference is shaped considering the input voltage envelope and forward duties.Finally,the effectiveness of the proposed rectifier is verified through simulations and experiments.

关键词： Buck-type rectifier commutation state controller design efficiency multiplex

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Multi-Scale Fusion Model Based on Gated Recurrent Unit for Enhancing Prediction Accuracy of State-of-Charge in Battery Energy Storage Systems

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Journal of Modern Power Systems and Clean Energy 2024年第2期12卷 405-414页

作者： Hao liu Fengwei Liang Tianyu Hu jichao Hong Huimin Ma School of Computer and Communication Engineering University of Science and Technology BeijingBeijingChina School of Mechanical Engineering University of Science and Technology BeijingBeijingChina IEEE

Accurate prediction of the state-of-charge(SOC)of battery energy storage system(BESS)is critical for its safety and lifespan in electric vehicles.To overcome the imbalance of existing methods between multi-scale feature fusion and global feature extraction,this paper introduces a novel multi-scale fusion(MSF)model based on gated recurrent unit(GRU),which is specifically designed for complex multi-step SOC prediction in practical BESSs.Pearson correlation analysis is first employed to identify SOC-related parameters.These parameters are then input into a multi-layer GRU for point-wise feature extraction.Concurrently,the parameters undergo patching before entering a dual-stage multi-layer GRU,thus enabling the model to capture nuanced information across varying time intervals.Ultimately,by means of adaptive weight fusion and a fully connected network,multi-step SOC predictions are rendered.Following extensive validation over multiple days,it is illustrated that the proposed model achieves an absolute error of less than 1.5%in real-time SOC prediction.

关键词： Electric vehicle battery energy storage system(BESS) state-of-charge(SOC)prediction gated recurrent unit(GRU) multi-scale fusion(MSF).

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Synergistic effects of planting density and nitrogen fertilization on chlorophyll degradation and leaf senescence after silking in maize

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The Crop Journal 2024年第2期12卷 605-613页

作者： Tianqiong Lan Lunjing Du Xinglong Wang Xiaoxu Zhan Qinlin liu Gui Wei Chengcheng Lyu Fan liu Jiaxu Gao Dongju Feng Fanlei Kong jichao Yuan Key Laboratory of Crop Physiology Ecologyand Cultivation SouthwestMinistry of AgricultureSichuan Agricultural UniversityChengdu 611130SichuanChina Chongqing Academy of Agricultural Sciences Chongqing 401329China College of Agronomy Sichuan Agricultural UniversityChengdu 611130SichuanChina

Regulating planting density and nitrogen(N)fertilization could delay chlorophyll(Chl)degradation and leaf senescence in maize cultivars.This study measured changes in ear leaf green area(GLA_(ear)),Chl content,the activities of Chl a-degrading enzymes after silking,and the post-silking dry matter accumulation and grain yield under multiple planting densities and N fertilization rates.The dynamic change of GLA_(ear)after silking fitted to the logistic model,and the GLA_(ear) duration and the GLAearat 42 d after silking were affected mainly by the duration of the initial senescence period(T_(1))which was a key factor of the leaf senescence.The average chlorophyllase(CLH)activity was 8.3 times higher than pheophytinase activity and contributed most to the Chl content,indicating that CLH is a key enzyme for degrading Chl a in maize.Increasing density increased the CLH activity and decreased the Chl content,T1,GLAear,and GLA_(ear) duration.Under high density,appropriate N application reduced CLH activity,increased Chl content,prolonged T1,alleviated high-density-induced leaf senescence,and increased post-silking dry matter accumulation and grain yield.

关键词： Density Nitrogen fertilization Leaf senescence Chlorophyll-degrading enzyme Logistic model

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Dealing with the Spatial Synthetic Heterogeneity of Aquifers in the North China Plain:A Case Study of Luancheng County in Hebei Province

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Acta Geologica Sinica(English Edition) 2012年第1期86卷 226-245页

作者： MA Rong SHI Jiansheng liu jichao The Institute of Hydrogeology and Environmental Geology ShijiazhuangHebei 050803

The complexity of alluvial-pluvial fan depositional systems makes the detailed characterization of their heterogeneity difficult, yet such a detailed characterization is commonly needed for construction of reliable groundwater models. Traditional models mainly focus on using a single aquifer property to qualitatively or semi-quantitatively characterize the heterogeneity of aquifer, so that they are unable to quantitatively reflect the synthetic heterogeneity of all aquifer properties. In this paper, we propose the heterogeneity synthetic index （HSI） for quantitative characterization of synthetic heterogeneity of an aquifer. The proposed calculation process involves four steps：（1） estimation of the hydraulic conductivity of a sediment sample using the cloud-Markov model, （2） establishment of the sedimentary microfacies distribution model through the Markov chain, （3） characterization of the distribution model of hydrogeological parameters using the improved sequential simulation method according to the ＂facies-controlled modeling＂ technique, and （4） application of the entropy weight method to calculate the weight coefficient of the above aquifer properties. The HSI of an aquifer is calculated by superposition of these models according to the corresponding weight coefficient. This approach was applied to the Luancheng aquifer deposit in the southeast Hutuo River alluvial-pluvial fan in the North China Plain （NCP）. The results have demonstrated that aquifer 3 which was formed in the middle Pleistocene has the strongest heterogeneity, with an HSI of 0.25-0.75. Aquifer 4 formed in the early Pleistocene shows an intermediate heterogeneity, with the HSI ranging 0.35-0.75. The weakest heterogeneity was found in aquifers 1 and 2 formed in the Holocene and late Pleistocene, with HSI values of 0.40-0.75 and 0.40- 0.80, respectively. The heterogeneity of all the four aquifers is relatively strong in the radial direction of the Huai River alluvial-pluvial fan due to the abrupt change of microfacies. In contrast, in the radia

关键词： aquifer heterogeneity hydraulic conductivity porosity Markov

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认知视域下生物学语境隐喻剖释——以《中国动物志》为例

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自然辩证法通讯 2024年第5期46卷 49-56页

作者：刘济超刘成盼郑守仪同济大学外国语学院上海200092 中国民航大学中欧航空工程师学院天津300300 中国科学院海洋研究所山东青岛266071

传统隐喻视角下,隐喻被长期束缚在修辞之茧中,而认知隐喻学为其打上了认知属性的标签。生物学语境隶属于宏观的科学语境,充溢着丰富的隐喻,且有其特定的运作机制。文章依托《中国动物志》,在认知视域下探究了隐喻的动因、催生机制、解... 详细信息

传统隐喻视角下,隐喻被长期束缚在修辞之茧中,而认知隐喻学为其打上了认知属性的标签。生物学语境隶属于宏观的科学语境,充溢着丰富的隐喻,且有其特定的运作机制。文章依托《中国动物志》,在认知视域下探究了隐喻的动因、催生机制、解码等方面。基于隐喻的旧词新意手段化解了生物学领域无限性与人类语言有限性之间的矛盾,而隐喻的真理性消除了跨域映射固有的语义冲突。体验现实主义将直接体验到的基本层次概念和意象图式内化于概念系统中,继而构筑更为复杂抽象的概念,籍此催生了隐喻。对于隐喻的解码需要相关联的常识系统和有效的凸显和隐藏,但同时需要留意跨域映射招致的信息减损和双重意象等滞碍。

关键词：生物学语境隐喻体验现实主义隐喻解码常识系统

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基于双惯导协同的误差参数估计与融合算法

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中国惯性技术学报 2024年第4期32卷 319-325,335页

作者：贾继超祁帅夏家和寇得民刘鑫航天科技集团九院16所西安710100 西安飞行自动控制研究所西安710065

针对无外界参考信息的双惯导系统长期使用后系统参数发生变化导致导航精度降低,且系统间缺少信息融合的问题,提出了一种同等精度双惯导协同误差估计与信息融合算法。首先以两套旋转式惯导间相对速度误差与位置误差作为观测量,建立包含... 详细信息

针对无外界参考信息的双惯导系统长期使用后系统参数发生变化导致导航精度降低,且系统间缺少信息融合的问题,提出了一种同等精度双惯导协同误差估计与信息融合算法。首先以两套旋转式惯导间相对速度误差与位置误差作为观测量,建立包含陀螺和加速度计零偏的导航误差模型。然后分析了不同转序下各状态量的可观测性,采用Kalman滤波对各参数进行有效估计,估计完成后对双惯导系统进行误差补偿及信息融合。仿真结果表明,所提算法对陀螺零偏估计精度优于0.002(°)/h,加速度计零偏估计精度优于4μg,在抑制误差发散的同时,提高了旋转式惯导导航精度。

关键词：双惯导系统旋转调制误差估计数据融合

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小众化科技知识传播的发展与相关建议探究——以有孔虫知识科普为视角

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科技管理研究 2024年第5期44卷 216-222页

作者：刘济超刘成盼郑守仪同济大学外国语学院上海200092 中国民航大学中欧航空工程师学院天津300300 中国科学院海洋研究所山东青岛266071

以我国有孔虫研究的科普工作为视角,梳理发展时期和传播渠道,反思传播局限,有针对性地提出科学普及与群众生活、圈层文化、科技创新协同发展的建议。期望在遵循小众化科技知识传播规律的基础上,运用契合自身特点与传播空间的方法与手段... 详细信息

以我国有孔虫研究的科普工作为视角,梳理发展时期和传播渠道,反思传播局限,有针对性地提出科学普及与群众生活、圈层文化、科技创新协同发展的建议。期望在遵循小众化科技知识传播规律的基础上,运用契合自身特点与传播空间的方法与手段,推动该类知识科普的积极发展。

关键词：小众化科技知识有孔虫科学普及科技传播

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Suitability assessment of deep groundwater for drinking, irrigation and industrial purposes in Jiaozuo City, Henan Province, north China

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Chinese Science Bulletin 2013年第25期58卷 3098-3110页

作者： SHI JianSheng MA Rong liu jichao ZHANG YiLong Institute of Hydrogeology and Environmental Geology

Groundwater has been a major natural resource for human consumption in north China. It is necessary to appreciate the suitability of deep groundwater for drinking, agricultural irrigation, and industrial uses in this region. To this end, a total of 47 groundwater samples were collected from the study area; by comparing the concentrations of different hydrochemical variables with quality standard values, the variable fuzzy set (VFS) was applied to calculate the groundwater quality index (GQI) for various purposes, respectively. Afterward GQI spatial distribution maps were constructed using a geographic information system (GIS) tool to delineate spatial variations of groundwater quality. In this case study, the GQI spatial distribution maps reveal that the areas covered by "Maximum Permissible" groundwater for varying purposes (drinking, irrigation, and industrial) is 1377.2; 2354.7; and 3854.8 km2, respectively. The groundwater in the eastern part of the study area is suitable for drinking, with the southwestern region as the irrigation water source; the entire study area is acceptable for use in industrial, except the western part of Jiaozuo City. Therefore, the GQI spatial distribution maps can provide useful information for non-technical decision makers for better sustainable groundwater resources management.

关键词：工业用途农业灌溉中国北方水饮用焦作市适宜性评价河南省地下水水质

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