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Phytoremediation of PAH-Contaminated Sediments by Potamogeton Crispus L. with Four Plant Densities

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Transactions of Tianjin University 2015年第5期21卷 440-445页

作者：孟凡波迟杰 School of Environmental Science and Engineering Tianjin University

In order to investigate the effect of plant density ofPotamogeton crispus L. on the remediation of sedi- ments contaminated by polycyclic aromatic hydrocarbons, a 54-day experiment with four plant densities （642, 1 604, 2 567 and 3 530 plants/m^2） was conducted. The results showed higher plant density with slower plant growth rate. Surface area per plant was the most sensitive root parameter to plant density. At the end of the 54-day experi- ment, planting P. crispus enhanced the dissipation ratios of phenanthrene and pyrene in sediments by 6.5%-26,2% and 0.95%-13.6%, respectively. The dissipation increment increased with increasing plant density. Plant uptake accounted for only a small portion of the dissipation increments. Furthermore, P. crispus could evidently improve sediment redox potentials, and strong positive correlations between root surface area and the redox potential as well as between the redox potentials and the dissipation ratios of phenanthrene and pyrene were obtained, indicating that the oxygen released by the roots ofP. crispus might be the main mechanism by which P. crispus enhanced the dis- sipation of PAHs in sediments.

关键词： polycyclic aromatic hydrocarbons (PAHs) phytoremediation plant density Potamogeton crispus L. sediments

To improve alignment of isoindigo-based conjugated polymer film by controlling contact line receding velocity

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chinese Chemical Letters 2017年第8期28卷 1663-1669页

作者： Shuai-jie chi Liang Chen Hong-Xiang Li Jian-Gang Liu Xin-Hong Yu Yan-Chun Han State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China University of the chinese Academy of Sciences Beijing 100049China

The macroscopic alignment of conjugated polymers with low grain boundary is essential to carrier transport. During film forming process, the match between contact line receding velocity and the critical alignment velocity is essential to get the alignment polymer film. In this paper, the contact line receding velocity of a D-A conjugated polymer film, isoindigo and bithiophene（IIDDT-C3）, was adjusted by solvent vapor content and film-formation temperature. Only when solvent vapor content was 0.3 m L and the film-formation temperature was 90C, the contact line receding velocity was in accordance with the critical alignment velocity, and the highest degree of alignment was attained in the IIDDT-C3 film, with the dichroic ratio up to 4.08. Fibers were aligned parallel with the direction of the contact line receding and the molecules of IIDDT-C3 adopted an edge-on orientation with the backbone parallel with the direction of fiber long axis. The p-p stacking distance between adjacent molecules was 3.63 ？.

关键词： IID-based conjugated polymers Alignment Contact line receding velocity Critical alignment velocity

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设备使用过程中的故障分布及可靠度变化分析

重庆建筑大学学报 2006年第5期28卷 51-54页

作者：池洁重庆交通大学管理学院重庆400074

通过对设备故障影响因素、故障分布主要类型、可靠性变化的分析,研究了设备故障的分布类型(指数分布函数,威布尔分布函数),可靠性变化的计算,同时结合具体的实例来分析如何确定故障分布类型,以及如何确定设备可以达到的可靠性水平,并根... 详细信息

通过对设备故障影响因素、故障分布主要类型、可靠性变化的分析,研究了设备故障的分布类型(指数分布函数,威布尔分布函数),可靠性变化的计算,同时结合具体的实例来分析如何确定故障分布类型,以及如何确定设备可以达到的可靠性水平,并根据实际数据得到了ZW-17/29空压机在使用过程中的故障分布函数、可靠度变化。为制定设备的技术管理和维修管理计划提供理论方法。

关键词：设备管理设备故障可靠度分布函数

Piperine regulates the circadian rhythms of hepatic clock gene expressions and gut microbiota in high-fat diet-induced obese rats

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Food Science and Human Wellness 2024年第3期13卷 1617-1627页

作者： Weiyun Zhang chi-Tang Ho Wenlian Wei jie Xiao Muwen Lu Guangdong Provincial Key Laboratory of Nutraceuticals and Functional Foods College of Food ScienceSouth China Agricultural UniversityGuangzhou 510642China Department of Food Science Rutgers UniversityNew Brunswick 08901USA

The interplay between the host circadian clock and microbiota has significant influences on host metabolism processes,and circadian desynchrony triggered by high-fat diet(HFD)is closely related to metabolic *** this study,the modulatory effects of piperine(PIP)on lipid metabolism homeostasis,gut microbiota community and circadian rhythm of hepatic clock gene expressions in obese rats were *** Sprague-Dawley(SD)rats were fed with normal diet(ND),HFD and HFD supplemented with PIP,*** 9 weeks,rats were sacrificed with tissue and fecal samples collected for circadian *** showed that chronic PIP administration ameliorated the obesity-induced alterations in lipid metabolism and dysregulation of hepatic clock gene expressions in obese *** gut microbial communities studied through 16S rRNA sequencing showed that PIP ameliorated the imbalanced nicrobiota and recovered the circadian rhythm of Lactobacillaceae,Desulfovibrionaceae,Paraprevotellaceae,and *** fecal metabolic profiles indicated that 3-dehydroshikimate,cytidine and lithocholyltaurine were altered,which were involved in the amino acid and fatty acid metabolism *** findings could provide theoretical basis for PIP to work as functional food to alleviate the lipid metabolism disorder,circadian rhythm misalignment,and gut microbiota dysbiosis with wide applications in the food and pharmaceutic industries.

关键词： Piperine Circadian clock Obesity Gut microbiota

A near-zero quiescent power breeze wake-up anemometer based on a rolling-bearing triboelectric nanogenerator

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Microsystems & Nanoengineering 2024年第2期10卷 241-249页

作者： Xianpeng Fu Zhichao Jiang jie Cao Zefang Dong Guoxu Liu Meiling Zhu chi Zhang CAS Center for Excellence in Nanoscience Beijing Key Laboratory of Micro-nano Energy and SensorBeijing Institute of Nanoenergy and NanosystemsChinese Academy of SciencesBeijing101400China School of Nanoscience and Engineering University of Chinese Academy of SciencesBeijing100049China Center on Nanoenergy Research Guangxi Colleges and Universities Key Laboratory of Blue Energy and Systems IntegrationSchool of Physical Science&TechnologyGuangxi UniversityNanning530004China Institute of Intelligent Flexible Mechatronics Jiangsu UniversityZhenjiang212013China College of Engineering Mathematics and Physical ScienceUniversity of ExeterExeterEX44QFUK

Wind sensors have always played an irreplaceable role in environmental information monitoring and are expected to operate with lower power consumption to extend service ***,we propose a breeze wake-up anemometer(B-WA)based on a rolling-bearing triboelectric nanogenerator(RB-TENG)with extremely low static *** B-WA consists of two RB-TENGs,a self-waking-up module(SWM),a signal processing module(SPM),and a wireless transmission *** two RB-TENGs are employed for system activation and wind-speed *** the ambient wind-speed exceeds 2 m/s,the wake TENG(W-TENG)and the SWM can wake up the system within 0.96 *** the same time,the SPM starts to calculate the signal frequency from the measured TENG(M-TENG)to monitor the wind speed with a sensitivity of 9.45 Hz/(m/s).After the wind stops,the SWM can switch off the B-WA within 0.52 s to decrease the system energy *** quiescent on-duty mode,the operating power of the B-WA is less than 30 nW,which can greatly extend the service lifetime of the *** integrating triboelectric devices and rolling bearings,this work has realized an ultralow quiescent power and self-waked-up wireless wind-speed monitoring system,which has foreseeable applications in remote weather monitoring,IoT nodes,and so on.

关键词： generator power service

Statistical study of magnetotail flux ropes near the lunar orbit

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Science china(Technological Sciences) 2016年第10期59卷 1591-1596页

作者： ZHAO Si Qi TIAN An Min SHI Quan Qi XIAO chi jie FU Sui Yan ZONG Qiu Gang WANG Hui Zi ZHANG Shuai ZHAO Shao jie PAN Dong Xiao TENG Shang Chun LIU Yi Xing TAN Kun Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment School of Space Science and PhysicsShandong University School of Physics Peking University School of Earth and Space Science Peking University

Flux-rope/TCR events near the magnetotail lunar orbit （-67RE 〈 GSM X＊〈 -39RE） were studied using magnetic-field and plasma data measured by THEMIS B and C between January 2011 and March 2012. The aberrant coordinate GSM＊, where the X＊ axis is rotated 4° relative to GSM-X, was used to count the occurrence rate. The number ratio of earthward to tailward events was about 3：5. Moreover, the event occurrence rate distribution showed a clear dawn-dusk asymmetry distribution, with dusk-side events accounting for 57.98%. A superposed epoch analysis of the flux-rope events showed that earthward events had a shorter duration in the leading than in the trailing part. Earthward events also displayed a lower temperature and a lower flow speed than tailward events. We studied the relationship between the event occurrence rate and geomagnetic activity level even further. The occurrence rate of tailward flux-rope/TCR events increases with increasing AE-index, whereas earthward events occur mainly in the relatively quiet period of geomagnetic activity （AE - 100-300 nT）. Flux-rope/TCR events identi- fied within a 10 mm time frame were treated as belonging to a single reconnection event. By comparing the occurrence rates of earthward and tailward events along X＊, we estimated the most likely location of the near-Earth reconnection site as X＊ = -36RE.

关键词： magnetotail flux rope TCR dawn-dusk asymmetry reconnection site

Characteristics of plankton Hg bioaccumulations based on a global data set and the implications for aquatic systems with aggravating nutrient imbalance

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Frontiers of Environmental Science & Engineering 2022年第3期16卷 121-133页

作者： Zhike Li jie chi Zhenyu Wu Yiyan Zhang Yiran Liu Lanlan Huang Yiren Lu Minhaz Uddin Wei Zhang Xuejun Wang Yan Lin Yindong Tong School of Environmental Science and Engineering Tianjin UniversityTianjin 300072China School of Economics and Management China University of PetroleumBeijing 102249China School of Environment and Natural Resource Renmin University of ChinaBeijing 100872China College of Urban and Environmental Sciences Peking UniversityBeijing 100871China Norwegian Institute for Water Research Oslo 0349Norway

The bioaccumulation of mercury(Hg)in aquatic ecosystem poses a potential health risk to human being and aquatic *** by plankton represent a crucial process of Hg transfer from water to aquatic food ***,the current understanding of major factors affecting Hg accumulation by plankton is *** this study,a data set of 89 aquatic ecosystems worldwide,including inland water,nearshore water and open sea,was *** factors influencing plankton Hg bioaccumulation(i.e.,plankton species,cell sizes and biomasses)were *** results indicated that total Hg(THg)and methylmercury(MeHg)concentrations in plankton in inland waters were significantly higher than those in nearshore waters and open *** factors for the logarithm of THg and MeHg of phytoplankton were 2.4–6.0 and 2.6–6.7 L/kg,respectively,in all aquatic *** could be further biomagnified by a factor of 2.1–15.1 and 5.3–28.2 from phytoplankton to *** MeHg concentrations were observed with the increases of cell size for both phyto-and zooplankton.A contrasting trend was observed between the plankton biomasses and BAF_(MeHg),with a positive relationship for zooplankton and a negative relationship for *** physiologic traits impose constraints on the rates of nutrients and contaminants obtaining process from ***,many aquatic ecosystems are facing rapid shifts in nutrient *** suggested that these potential influences on the growth and composition of plankton should be incorporated in future aquatic Hg modeling and ecological risk assessments.

关键词： Plankton Hg bioaccumulation Physiological characteristics A cross-system analysis Nutrient compositions Global data set

Ultra-Robust and High-Performance Rotational Triboelectric Nanogenerator by Bearing Charge Pumping

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Energy & Environmental Materials 2024年第2期7卷 343-349页

作者： Xianpeng Fu Yuhan Qin Zhi Zhang Guoxu Liu jie Cao Beibei Fan Zhaozheng Wang Zheng Wang chi Zhang CAS Center for Excellence in Nanoscience Beijing Key Laboratory of Micro-nano Energy and SensorBeijing Institute of Nanoenergy and NanosystemsChinese Academy of SciencesBeijing 101400China School of Nanoscience and Technology University of Chinese Academy of SciencesBeijing 100049China Center on Nanoenergy Research School of Physical Science and TechnologyGuangxi UniversityNanning 530004China

As an emerging technology to convert environmental high-entropy energy into electrical energy,triboelectric nanogenerator(TENG)has great demands for further enhancing the service lifetime and output performance in practical ***,an ultra-robust and high-performance rotational triboelectric nanogenerator(R-TENG)by bearing charge pumping is *** R-TENG composes of a pumping TENG(P-TENG),an output TENG(O-TENG),a voltage-multiplying circuit(VMC),and a buffer *** P-TENG is designed with freestanding mode based on a rolling ball bearing,which can also act as the rotating mechanical energy *** output low charge from the P-TENG is accumulated and pumped to the non-contact O-TENG,which can simultaneously realize ultralow mechanical wear and high output *** matched instantaneous power of R-TENG is increased by 32 times under 300 r/***,the transferring charge of R-TENG can remain 95%during 15 days(6.4×10^(6)cycles)continuous *** work presents a realizable method to further enhance the durability of TENG,which would facilitate the practical applications of high-performance TENG in harvesting distributed ambient micro mechanical energy.

关键词： bearing charge pumping triboelectric nanogenerators ultralow mechanical wear ultra-robust voltage-multiplying circuit

OHMEFENTANYL——A NEW AGONIST FOR μ-OPIATE RECEPTOR

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Science in china,Ser.B 1985年第5期28卷 504-511页

作者：徐珩陈洁池志强 Shanghai Institute of Materia Medica Academia Sinica

Ohmefentanyl （F 7302, N[1-（β-hydroxy-β-phenylethyt）-3-methyl-4-piperidyl]-N-phenylpropionamide） is a potent synthetic analgesic agent. The analgesic activity of ohmefentanyl in mice is 6300 times more potent than that of morphine. The potency of ohmefentanyl in competing with specific binding of 3H-naloxone is reduced by Na+ （100 mM） and GTP（50μM）, thus suggesting the agonist properties of this compound. Binding characteristics of 3Hohmefentanyl with mice brain P2 fraction are studied. An important saturable, specific and reversible binding is demonstrated. Scatchard analysis indicates the existence of two classes of binding sites （KD1=0.32nM, KD2=3.91nM）. Various opiate drugs strongly inhibit the binding of 3H-ohmefentanyl, but nonopiate drugs have negligible affinity. Comparison of the relative potencies of morphine, DSTLE（Tyr-D-Ser-Gly-Phe-Leu-Thr, a specific ligand for the δ-opiate receptor） and ohmefentanyl in competing with 3H-dihydromorphine （μ） and 3H[D-Ala2, D-Leu5]-enkephalin (

关键词： OPIATE RECEPTOR A NEW AGONIST FOR than DADLE