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Zinc, copper, and strontium isotopic variability in the Baiyangping Cu–Pb–Zn–Ag polymetallic ore field, Lanping Basin, Southwest China

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Acta Geochimica 2021年第4期40卷 557-574页

作者： Caixia Feng shen Liu Guoxiang Chi Xianwu Bi Ruizhong Hu Ian MCoulson State Key Laboratory of Continental Dynamics Department of GeologyNorthwest University229 Taibai RoadXi’an 710069China Departments of Geology University of Regina3737 Wascana ParkwayReginaSK S4S 0A2Canada Institute of Geochemistry Chinese Academy of Sciences99 Lincheng RoadGuiyang 550002China

The Baiyangping Cu-Ag polymetallic ore district is located in the northern part of the Lanping-Simao foreland fold belt,between the Jinshajiang-Ailaoshan and Lancangjiang faults,and the deposit can be divided into eastern and western ore *** upon microscope observation of ore minerals and analysis of zinc,copper,and strontium isotope composition,we conclude that:(1)the zinc isotopic compositions of sphalerite from the eastern and western ore belt of the Baiyangping polymetallic ore deposits are enriched in both the heavy(-0.09‰ to+0.15‰) and light(-0.19‰ to-0.01‰)zinc *** fractionation is likely the additional factor controlling the observed temporal and spatial variations in zinc isotopes in the two studied ore *** zinc isotopic composition in the Baiyangping polymetallic Pb-Zn deposits may have the same fractionation as that of magmatic-hydrothermal,VHMS,SEDEX,and MVT deposits,as demonstrated by geological and other geochemical evidence;(2) the range of δ^(65)Cu in massive tetrahedrite is from-0.06‰ to+0.12 ‰ that relates to the early stages of ore-formation,which are higher than that of venial chalcopyrite(from-0.72‰ to-0.07‰)formed at a late ore-forming stage in the western ore *** ore-forming stages and alteration or leaching processes are likely the main factors controlling the observed variations in copper isotopes in the western ore zone;(3) the ^(87)Sr/^(86)Sr value of hydrothermal calcite in eastern(0.7080-0.7093) and western(0.7085-0.7113) ore belt suggested that mineralization of early calcite,with^(87)Sr/^(86)Sr values much higher than in ancient Late Triassic seawater,may be related to recrystallization from a radiogenic Sr-rich or silicifying fluid,either from the strata that the ore-forming fluid flows through or from other fluids.

关键词： Zn-Cu-Sr isotopic variation Cu-Pb-Zn-Ag poly-metallic ore deposit Baiyangping Lanping Basin

Characterization of impurities in the bulk drug lisinopril by liquid chromatography/ion trap spectrometry

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2008年第5期9卷 385-390页

作者： Pei-xi ZHU Dan-hua WANG Cui-rong SUN Zhi-quan shen Department of Chemistry Zhejiang University Hangzhou 310027 China Department of Polymer Science and Engineering Zhejiang University Hangzhou 310027 China

Two trace impurities in the bulk drug lisinopril were detected by means of high-performance liquid chromatography coupled with mass spectrometry （HPLC/MS） with a simple and sensitive method suitable for HPLC/MSn analysis. The fragmentation behavior of lisinopfil and the impurities was investigated, and two unknown impurities were elucidated as 2-（6-amino- l-（l-carboxyethylamino）- l-oxohexan-2-ylamino）-4-phenylbutanoic acid and 6-amino-2-（l-carboxy-3-phenylpropylamino）-hexanoic acid on the basis of the multi-stage mass spectrometry and exact mass evidence, The proposed structures of the two unknown impurities were further confirmed by nuclear magnetic resonance （NMR） experiments after preparative isolation.

关键词： Lisinopril Impurities High-performance liquid chromatography (HPLC) Multi-stage mass spectrometry (MS^n)

Energy Balance of Irrigated Intercropping Field in the Middle Reaches of Heihe River Basin

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Chinese Geographical Science 2006年第3期16卷 243-248页

作者： WU Jinkui DING Yongjian WANG Genxu shen Yongping Yusuke YAMAZAKI Jumpei KUBOTA Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China The Laboratory of Climate Study of China Meteorological Administration Beijing 100041 China Research Institute for Humanity and Nature Kyoto 602-0778 Japan

Based on the experiments conducted in an irrigated intercropping field in Zhangye Oasis in the middle reaches of Heihe River basin in 2004, the characteristics of radiation budget are analyzed. Furthermore, energy balance is cal- culated by using Bowen-Ratio Energy Balance (BREB) method. The results show that the ratio of the absorbed radiation to the incoming short radiation in intercropping crop canopy-soil system is increasing with growing stages, from 0.81 in the initial growing stage (IGS) to 0.86 in the late growing stage (LGS). The net radiation, which is smaller in IGS, in- creases rapidly in the first period of the middle growing stage (MGS) and reaches the maximum value in the second period of MGS. It then somewhat decreases in LGS. The ratio of net radiation to total radiation has a similar trend with the net radiation. In the whole growing stages, latent heat flux, which takes up 70% or so of the net radiation, is the dominant item in energy balance. Sensible heat flux shares 20% of the net radiation and soil heat flux has a percentage of 10%. The characteristics of heat balance vary distinctly in different growing stages. In IGS, the ratios of latent heat flux, sensible heat flux and soil heat flux to net radiation are 44.5%, 23.8% and 31.7% respectively. In MGS, with the in- creasing of latent heat flux and the decreasing of sensible heat flux and soil heat flux, the ratios turn into 84.4%, 6.3% and 9.3%. In LGS, the soil heat flux maintains 0W/m2 or so, and latent heat flux and sensible heat flux take up 61.4% and 38.6% respectively. The energy balance also shows an obvious daily variation characteristic.

关键词： radiation budget energy balance intercropping field Heihe River basin

An efficient and recyclable iron(III)-containing imidazolium salt catalyst for cross-coupling of aryl Grignard reagents with alkyl halides

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Chinese Science Bulletin 2012年第16期57卷 1953-1958页

作者： YAN ChunHui WANG LinLin GAO HuanHuan SUN HongMei shen Qi The Key Laboratory of Organic Synthesis of Jiangsu Province College of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhou 215123China

1,3-Bis(2,6-diisopropylphenyl)imidazolium chloride, [DIPrim]Cl, was used to produce a novel iron(III)-containing imidazolium salt [DIPrim][FeCl 4 ], which included a N,N-diarylimidazolium cation (R = 2,6-diisopropylphenyl), [DIPrim] + , and tetrachloroferrate(III) anion, [FeCl 4 ]. This compound was an effective and easy-to-use catalyst for the cross-coupling of aryl Grignard reagents with primary and secondary alkyl halides bearing -hydrogens. After simply decanting the cross-coupling product in the ether layer, [DIPrim][FeCl 4 ] could be reused in at least four successive runs without significant loss of catalytic activity.

关键词：格氏试剂咪唑盐催化剂交叉偶联可回收卤代烷铁交叉耦合

Survey of information security

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Science in China(Series F) 2007年第3期50卷 273-298页

作者： shen ChangXiang ZHANG HuangGuo FENG DengGuo CAO ZhenFu HUANG JiWu Computing Technology Institute of China Navy Beijing 100841 China School of Computer Wuhan University Wuhan 430072 China Institute of Software Chinese Academy of Sciences Beijing 100080 China Department of Computer Science and Technology Shanghai Jiaotong University Shanghai 200030China Information Technology Institute Zhongshan University Guangzhou 510275 China

The 21st century is the age of information when information becomes an important strategic resource. The information obtaining, processing and security guarantee capability are playing critical roles in comprehensive national power, and information security is related to the national security and social stability. Therefore, we should take measures to ensure the information security of our country. In recent years, momentous accomplishments have been obtained with the rapid development of information security technology. There are extensive theories about information security and technology. However, due to the limitation of length, this article mainly focuses on the research and development of cryptology, trusted computing, security of network, and information hiding, etc.

关键词： information security cryptology trusted computing network security information hiding

Cinnamate-functionalized hyperbranched polymer as liquid crystal photo-alignment layer

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Chinese Chemical Letters 2008年第9期19卷 1131-1134页

作者： Bin Jun shen Zheng Xie Ya Ning He Yan Qing Lian Institute of Polymer Research Department of Chemical Engineering Laboratory of Advanced Materials Tsinghua University Beijing 100084 China

In this work, 4-methoxylcinnamoyl chloride was reacted with a commercial hyperbranched polymer （Boltom-TM H30） to prepare a hyperbranched photosensitive polymer （H30-Ci）. The polymer was characterized by UV absorption spectrum and 1H- NMR spectrum. After processed by Linearly Polarized Polymerization （LPP） method, the spin-coated films of H30-Ci were used as photo-alignment layers to assemble liquid crystal （LC） cells containing nematic liquid crystal （5CB）. The observation by polarized microscope showed that the H30-Ci blended with a linear polymer （BP-AN-Ci） photo-alignment layers could align LC molecules in a very uniform way.

关键词： Hyperbranched polymer Photo-alignment layer Linearly polarized polymerization (LPP) Liquid crystal display

Rumination recognition method of dairy cows based on the change of noseband pressure

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Information Processing in Agriculture 2020年第4期7卷 479-490页

作者： Weizheng shen Aijing Zhang Yu Zhang Xiaoli Wei Jian Sun College of Electricity and Information Northeast Agricultural UniversityHarbin 150030China

Rumination is closely related to ruminant’s health and welfare,so it is very important to monitor *** monitoring equipment based on chewing and swallowing audio is easy to be affected by ambient noise,equipment based on acceleration sensor is not easy to monitor number of cuds and other information,equipment based on video monitoring has high cost and is easy to be affected by weather and other cows,while equipment based on chewing pressure can accurately record the chewing pressure of dairy cows,and use related processing technology to obtain the number of cuds and other *** the related research,the peak value and interval of masticatory pressure peak in time domain were used to identify *** view of the problem that the standard of pressure peak was not well defined due to the different head size and masticatory strength of different age and different breed cows,this paper proposed a method to identify the number of rumination,duration of rumination and number of cuds of cows by using standard deviation and noseband pressure signal frequency *** accurate and stable frequency spectrum range of rumination noseband pressure signal was obtained by frequency spectrum analysis,and the interference of feeding noseband pressure signal to rumination noseband pressure signal was eliminated by using standard *** with the direct observation,the results showed that the recognition accuracy of the method proposed in this paper were 100%,94.2%and 94.45%for the number of rumination,duration of rumination and number of cuds respectively,and the average absolute errors were 0,2.0029%and 2.5623%respectively,which showed that the method can accurately identify the rumination information of dairy cows.

关键词： Rumination Noseband pressure Standard deviation Characteristic frequency

Optimal day-ahead scheduling strategy of microgrid considering regional pollution and potential load curtailment

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Global Energy Interconnection 2024年第6期7卷 749-760页

作者： Xie, Xinghua Yang, Hejun Wang, Bo Ma, Yinghao Zhang, Dabo shen, Yuming Anhui Province Key Laboratory of Renewable Energy Utilization and Energy Saving Hefei University of Technology Hefei 230009 China Hangzhou Science and Technology development branch Zhejiang Dayou Industrial Co. Ltd. Zhejiang Hangzhou 310051 China Institute of Economy and Technology State Grid Anhui Electric Power Co. Ltd. Hefei 230071 China

With the frequent occurrence of global warming and extreme severe weather, the transition of energy to cleaner, and with lower carbon has gradually become a consensus. Microgrids can integrate multiple energy sources and consume renewable energy locally. The amount of pollutants emitted during the operation of the microgrids become an important issue to be considered. This study proposes an optimal day-ahead scheduling strategy of microgrid considering regional pollution and potential load curtailment. First, considering the operating characteristics of microgrids in islanded and grid- connected operation modes, this study proposes a regional pollution index (RPI) to quantify the impact of pollutants emitted from microgrid on the environment, and further proposes a penalty mechanism based on the RPI to reduce the microgrid's utilization on non-clean power supplies. Second, considering the benefits of microgrid as the operating entity, utilizing a direct load control (DLC) enables microgrid to enhance power transfer capabilities to the grid under the penalty mechanism based on RPI. Finally, an optimal day-ahead scheduling strategy which considers both the load curtailment potential of curtailable loads and RPI is proposed, and the results show that the proposed optimal day-ahead scheduling strategy can effectively inspire the curtailment potential of curtailable loads in the microgrid, reducing pollutant emissions from the microgrid. © 2024

关键词： Microgrid Demand response Direct load control Pollutant emission

Imposing Active Sources during High-Frequency Passive Surface-Wave Measurement

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Engineering 2018年第5期4卷 685-693页

作者： Feng Cheng Jianghai Xia Chao shen Yue Hu Zongbo Xu Binbin Mi Subsurface Imaging and Sensing Laboratory Institute of Geophysics and Geomatics China University of Geosciences Wuhan 430074 China School of Earth Sciences Zhejiang University Hangzhou 310027 China School of Measurement and Testing Engineering China Jiliang University Hangzhou 310018 China Department of Geosciences Boise State University Boise ID 83725 USA

Passive surface-wave utilization has been intensively studied as a means of compensating for the short-age of low-frequency information in active surface-wave measurement, In general, passive surface-wave methods cannot provide phase velocities up to several tens of hertz; thus, active surface-wave methods are often required in order to increase the frequency range, To reduce the amount of field work, we pro-pose a strategy for a high-frequency passive surface-wave survey that imposes active sources during con-tinuous passive surface-wave observation; we call our strategy ＂mixed-source surface-wave （MSW） measurement,＂ Short-duration （within 10 min） passive surface waves and mixed-source surface waves were recorded at three sites with different noise levels： namely, inside a school, along a road, and along a railway, Spectral analysis indicates that the high-frequency energy is improved by imposing active sources during continuous passive surface-wave observation, The spatial autocorrelation （SPAC） method and the multichannel analysis of passive surface waves （MAPS） method based on cross-correlations were performed on the recorded time sequences, The results demonstrate the flexibility and applicability of the proposed method for high-frequency phase velocity analysis, We suggest that it will be constructive to perform MSW measurement in a seismic investigation, rather than exclusively performing either active surface-wave measurement or passive surface-wave measurement,

关键词： Passive surface wave Active surface wave High frequency Mixed-source surface wave Spatial autocorrelation Multichannel analysis of passive surface waves