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Aquatic toxicity of di (2-eihylhexyl) phthalate to duckweeds

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Journal of Shanghai University(English Edition) 2010年第2期14卷 100-105页

作者：徐刚刘宁吴明红郭瑞云周佳欣施文彦李发生 School of Environmental and Chemical Engineering Shanghai University Department of Soil Pollution Control Chinese Research Academy of Environmental Sciences

This study is concerned with the effects of di （2-ethylhexyl） phthalate （DEHP） on two kinds of duckweeds （Spirodela polyrhiza and Lemna minor）.The results indicate that DEHP has aquatic toxicity to Spirodela polyrhiza at 0.4 mg/L and to Lemna minor at over 0.1 mg/L by changing their physiologic-biochemical *** contents of duckweed chlorophyll and soluble protein decrease with increasing DEHP concentration after 7 d of *** shows the stimulating role in catalase （CAT） and superoxide dismutase （SOD） systems at relative low *** 0.01 mg/L and 0.005 mg/L,SOD activities of Spirodela polyrhiza and Lemna minor reach their peak values respectively,while CAT activity reaches its maximum value at 0.05 mg/L and 0.01 mg/*** DEHP levels are too high,the protection enzyme system would be destroyed and plant growth is *** analysis of malondialdehyde （MDA） and Fourier transform infrared spectroscopy manifest that DEHP could affect the tested duckweeds by destroying its cell membranes,and Spirodela polyrhiza is more resistant to DEHP exposure than Lemna minor.

关键词： di (2-ethylhexyl) phthalate (DEHP) duckweed aquatic toxicity antioxidant enzyme

Identifying the driving factors of sediment delivery ratio on individual flood events in a long-term monitoring headwater basin

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Journal of Mountain Science 2018年第8期15卷 1825-1835页

作者： WANG Ling-ling YAO wen-yi TANG jia-liang WANG wen-long HOU xin-xin Yellow River Institute of Hydraulic Research Key Laboratory of the Loess Plateau Soil Erosion and Water Loss Process and Control of Ministry of Water Resources College of Resource and Environment Northwest A & F University Institute of Mountain Hazards and Environment Chinese Academy of Sciences

The Sediment Delivery Ratio(SDR) has multi-fold environmental implications both in evaluating the soil and water losses and the effectiveness of conservation measures in watersheds. Various factors, including hydrological regime and watershed properties, may influence the SDR at interannual timescales. However, the effect of certain important dynamic factors, such as rainfall peak distribution, runoff erosion power and sediment bulk density, on the sediment delivery ratio of single flood events(SDRe) has received little attention. The Qiaogou headwater basin is in the hilly-gully region of the Chinese Loess Plateau, and it encompasses a 0.45 km^2 catchment. Three large-scale field runoff plots at different geomorphological positions were chosen to obtain the observation data, and the 20-year period between 1986 and 2005 is presented. The results showed that the SDRe of the Qiaogou headwaters varied from 0.49 to 2.77. Among the numerous influential factors, rainfall and runoff were the driving factors causing slope erosion and sediment transport. The rainfall erosivity had a significant positive relationship with the sediment transport modulus(R^2=0.85, P<0.01) but had no significant relationship with SDRe. The rainfall peak coefficient was significantly positively correlated with the SDRe(R^2=0.64, P<0.05), indicating the influence of rainfall energy distribution on the SDRe. The runoff erosion power index was not only significantly related to the sediment transport modulus(R^2=0.84, P<0.01) but also significantly related to the SDRe(R^2=0.57, P<0.01). In addition, the relative bulk density was significantly related to the SDRe, indicating that hyper-concentrated flow characteristics contributed to more transported sediment in the catchment. Thus, the rainfall peak coefficient, runoff erosion power and sediment relative bulk density could be used as dynamic indexes to predict the SDRe in the hilly areas of the Chinese Loess Plateau.

关键词： Sediment delivery ratio Single flood events Rainfall erosivity Runoff erosion power Hyper-concentrated flow

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基于隐性句逗号识别的汉语长句机器翻译

外语学刊 2025年第1期 39-46页

作者：冯文贺李熳佳张文娟广东外语外贸大学外国语言学及应用语言学研究中心语言工程与计算实验室广州510420 广州理工学院计算机科学与工程学院广州510420

长句翻译一直是机器翻译的难题。本文根据汉语中相当数量的逗号和句号可相互转化的特点,提出“隐性句号”和“隐性逗号”概念,并实现其自动识别,以将汉语长句变为短句用于汉英机器翻译。为此,首先通过人工与半监督学习结合方法构建一个... 详细信息

长句翻译一直是机器翻译的难题。本文根据汉语中相当数量的逗号和句号可相互转化的特点,提出“隐性句号”和“隐性逗号”概念,并实现其自动识别,以将汉语长句变为短句用于汉英机器翻译。为此,首先通过人工与半监督学习结合方法构建一个隐性句逗数据集,实现基于预训练模型的隐性句逗识别方法,其中性能最好的Hierarchical BERT作为后续应用模型。进而,实现基于隐性句逗识别的汉英机器翻译方法。在新闻和文学公开翻译测试语料上基于预训练机器翻译模型的实验表明,对于汉语长句的英译,本文方法相比基准翻译的BLEU值整体有所提高,而且在相对稳健机器翻译模型上,呈现为句子越长本文方法效果越明显。

关键词：机器翻译长句翻译隐性句逗号汉语长句逗号识别句内标点

Dynamics and rebound behavior analysis of flexible tethered satellite system in deployment and station-keeping phases

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Defence Technology（防务技术） 2022年第3期18卷 509-523页

作者： Yue Zhang xin jiang Zheng-feng Bai jia-wen Guo Cheng Wei School of Space Science and Technology Xidian UniversityXi'an710126China School of Astronautics Harbin Institute of TechnologyHarbin150001China Department of Mechanical Engineering Harbin Institute of TechnologyWeihai264209China

The tether deployment of a tethered satellite system involves the consideration of complex dynamic properties of the tether,such as large deformation,slack,and even rebound,and therefore,the dynamic modelling of the tether is necessary for performing a dynamic analysis of the *** a variablelength tether element,the absolute nodal coordinate formulation(ANCF)in the framework of the arbitrary Lagrange-Euler(ALE)description was used to develop a precise dynamic model of a tethered *** model considered the gravitational gradient force and Coriolis force in the orbital coordinate frame,and it was validated through numerical *** the presence of dynamic constraints,a deployment velocity of the tether was obtained by an optimal *** the simulation,rebound behavior of the tethered satellite system was observed when the ANCF-ALE model was ***,the rebound behavior cannot be predicted by the traditional dumbbell ***,an improved optimal deployment velocity was *** results indicated that the rebound phenomenon was eliminated,and smooth deployment as well as a stable state of the station-keeping process were ***,the swing amplitude in the station-keeping phase decreased when a deployment strategy based on the improved optimal deployment velocity was used.

关键词： Tethered satellite system Dynamic model Rebound Deployment ANCF-ALE

Low-temperature-processed metal oxide electron transport layers for efficient planar perovskite solar cells

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Rare Metals 2021年第10期40卷 2730-2746页

作者： jia-xing Song xin-xing Yin Zai-Fang Li Yao-wen Li China-Australia Institute for Advanced Materials and Manufacturing(IAMM) Jiaxing UniversityJiaxing 314001China Laboratory of Advanced Optoelectronic Materials College of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhou 215123China

As a promising photovoltaic technology, perovskite solar cells(pero-SCs) have developed rapidly over the past few years and the highest power conversion efficiency is beyond 25%. Nowadays, the planar structure is universally popular in pero-SCs due to the simple processing technology and low-temperature *** transport layer(ETL) is verified to play a vital role in the device performance of planar pero-SCs. Particularly, the metal oxide(MO) ETL with low-cost, superb versatility, and excellent optoelectronic properties has been widely studied. This review mainly focuses on recent developments in the use of low-temperature-processed MO ETLs for planar pero-SCs. The optical and electronic properties of widely used MO materials of TiO_(2), ZnO, and SnO_(2), as well as the optimizations of these MO ETLs are briefly introduced. The commonly used methods for depositing MO ETLs are also discussed. Then, the applications of different MO ETLs on pero-SCs are ***, the challenge and future research of MO-based ETLs toward practical application of efficient planar peroSCs are proposed.

关键词： Perovskite solar cell Electron transport layer Metal oxide Low temperature Planar

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微生物菌群调控人畜共患结核病的研究进展

动物医学进展 2025年第1期46卷 91-96页

作者：许霄峰张广智鑫婷叶建新张建伟贾丽钱佳豪温贺飞吴慧光蒋卉丁家波中国农业科学院北京畜牧兽医研究所北京100097 农业农村部动物生物安全风险预警及防控重点实验室(北方) 北京100193 扬州大学兽医学院江苏扬州225009 北京市畜牧总站北京100193 河北农业大学动物医学院河北保定071000 河北省遵化市农业农村局河北唐山064200

目前,人畜共患结核病(zTB)仍是世界上最重要的细菌传染性疫病之一,严重威胁人和动物健康以及公共卫生安全。机体数量庞大的微生物菌群积极参与着机体的发育、免疫调控、代谢等。研究发现微生物菌群和zTB的发生、发展、治疗、疫苗免疫具... 详细信息

目前,人畜共患结核病(zTB)仍是世界上最重要的细菌传染性疫病之一,严重威胁人和动物健康以及公共卫生安全。机体数量庞大的微生物菌群积极参与着机体的发育、免疫调控、代谢等。研究发现微生物菌群和zTB的发生、发展、治疗、疫苗免疫具有紧密的相关性,现已成为诸多领域中的研究热点。菌群对zTB进程的调控可通过诸多途径直接或间接地进行,如菌群稳态、代谢物及对免疫的调控等。基于此,论文综述了目前微生物菌群与zTB相关研究的最新进展,重点讨论了肠道菌群和肺部菌群与zTB的关联及调节机制,分析了肠-肺轴相互作用、菌群代谢产物对zTB的影响,探讨了通过调节宿主的菌群组成和功能对预防和辅助治疗结核病的潜在价值,旨在为zTB防控提供理论基础和借鉴。

关键词：人畜共患结核病肠道微生物菌群肠-肺轴益生菌

Effects of aggregate size distribution and carbon nanotubes on the mechanical properties of cemented gangue backfill samples under true triaxial compression

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 311-324页

作者： Qian Yin Fan wen Zhigang Tao Hai Pu Tianci Deng Yaoyao Meng Qingbin Meng Hongwen Jing Bo Meng jiangyu Wu State Key Laboratory of Intelligent Construction and Healthy Operation and Maintenance of Deep Underground Engineering China University of Mining and TechnologyXuzhou 221116China State Key Laboratory of Mining Response and Disaster Prevention and Control in Deep Coal Mines Anhui University of Science and TechnologyHuainan 232001China State Key Laboratory for Geomechanics&Deep Underground Engineering China University of Mining and Technology(Beijing)Beijing 100083China Key Laboratory of xinjiang Coal Resources Green Mining Ministry of EducationXinjiang Institute of EngineeringUrumqi 830023China

The mechanical behavior of cemented gangue backfill materials(CGBMs)is closely related to particle size distribution(PSD)of aggregates and properties of cementitious ***,the true triaxial compression tests,CT scanning,SEM,and EDS tests were conducted on cemented gangue backfill samples(CGBSs)with various carbon nanotube concentrations(P_(CNT))that satisfied fractal theory for the PSD of *** mechanical properties,energy dissipations,and failure mechanisms of the CGBSs under true triaxial compression were systematically *** results indicate that appropriate carbon nanotubes(CNTs)effectively enhance the mechanical properties and energy dissipations of CGBSs through micropore filling and microcrack bridging,and the optimal effect appears at P_(CNT)of 0.08wt%.Taking PSD fractal dimension(D)of 2.500 as an example,compared to that of CGBS without CNT,the peak strength(σ_(p)),axial peak strain(ε_(1,p)),elastic strain energy(Ue),and dissipated energy(U_(d))increased by 12.76%,29.60%,19.05%,and90.39%,***,excessive CNTs can reduce the mechanical properties of CGBSs due to CNT agglomeration,manifesting a decrease inρ_(p),ε_(1,p),and the volumetric strain increment(Δε_(v))when P_(CNT)increases from 0.08wt%to 0.12wt%.Moreover,the addition of CNTs improved the integrity of CGBS after macroscopic failure,and crack extension in CGBSs appeared in two modes:detour and pass through the ***σ_(p)and U_(d)firstly increase and then decrease with increasing D,and porosity shows the opposite ***ε_(1,p)andΔε_(v)are negatively correlated with D,and CGBS with D=2.150 has the maximum deformation parameters(ε_(1,p)=0.05079,Δε_(v)=0.01990)due to the frictional slip effect caused by coarse *** increasing D,the failure modes of CGBSs are sequentially manifested as oblique shear failure,"Y-shaped"shear failure,and conjugate shear failure.

关键词： cemented gangue backfill materials particle size distribution true triaxial compression test carbon nanotubes mechanical properties failure modes

Combustion characteristics of unburned pulverized coal and its reaction kinetics with CO2

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International Journal of Minerals,Metallurgy and Materials 2019年第7期26卷 811-821页

作者： Dong-wen Xiang Feng-man Shen jia-long Yang xin jiang Hai-yan Zheng Qiang-jian Gao jia-xin Li School of Metallurgy Northeastern University Shenyang 110819 China School of Metallurgical Engineering Anhui University of Technology Ma’anshan 243002 China

The combustion characteristics of two kinds of unburned pulverized coal (UPC) made from bituminous coal and anthracite were investigated by thermogravimetric analysis under air. The reaction kinetics mechanisms between UPC and CO2 in an isothermal experiment in the temperature range 1000–1100°C were investigated. The combustion performance of unburned pulverized coal made from bituminous coal (BUPC) was better than that of unburned pulverized coal made from anthracite (AUPC). The combustion characteristic indexes (S) of BUPC and AUPC are 0.47 × 10^-6 and 0.34 × 10^-6 %2·min^-2·°C^-3, respectively, and the combustion reaction apparent activation energies are 91.94 and 102.63 kJ·mol^-1, respectively. The reaction mechanism of BUPC with CO2 is random nucleation and growth, and the apparent activation energy is 96.24 kJ·mol^-1. By contrast, the reaction mechanism of AUPC with CO2 follows the shrinkage spherical function model and the apparent activation energy is 133.55 kJ·mol^-1.

关键词： unburned pulverized coal combustion characteristics reactivity reaction mechanism apparent activation energy

基于地理分区的陕北黄土高原生态系统服务权衡/协同的尺度效应研究

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水土保持研究 2025年第1期32卷 305-315页

作者：温昕王继军韩晓佳中国科学院水土保持与生态环境研究中心陕西杨凌712100 中国科学院水利部水土保持研究所陕西杨凌712100 西北农林科技大学水土保持研究所陕西杨凌712100 中国科学院大学北京100049 中国科学院生态环境研究中心北京100085

[目的]明晰生态系统服务的权衡/协同关系,保证生态系统服务长期有效供应,实现流域生态保护与高质量发展。[方法]以典型退耕区陕北黄土高原为例,利用1990-2020年土地利用变化数据,基于InVEST模型量化4种关键生态系统服务即碳储量、产水... 详细信息

[目的]明晰生态系统服务的权衡/协同关系,保证生态系统服务长期有效供应,实现流域生态保护与高质量发展。[方法]以典型退耕区陕北黄土高原为例,利用1990-2020年土地利用变化数据,基于InVEST模型量化4种关键生态系统服务即碳储量、产水量、土壤保持量和生境质量的时空分布特征,通过相关性分析探讨了各类生态系统服务间的权衡/协同关系和呈现的尺度特征。[结果](1)1990-2020年碳储量和生境质量处于不断增加的趋势,产水量和土壤保持量呈现先降低后增加总体增加的趋势,空间上呈东南略低西北略高的分布。(2)陕北黄土高原生态系统服务以协同作用为主,且在1990-2020年协同效应不断增强,权衡作用主要发生在产水量与其他生态系统服务之间,权衡作用的区域主要分布在研究区西部和东北部地区。(3)生态系统服务间的权衡/协同作用存在着空间尺度效应,随着空间尺度的增加,相关性逐渐增强而显著性有所下降,且作用关系的方向性会发生改变。[结论]陕北黄土高原生态系统服务以协同为主,生态系统服务间的权衡/协同作用存在着空间尺度效应。

关键词：生态系统服务权衡/协同作用尺度效应地理分区陕北黄土高原