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化学需氧量电化学传感器研究

分析化学 2024年第9期52卷 1298-1306页

作者：貟姗王磊万立国彭振宇王鸿昌翟俊峰董绍俊中国科学院长春应用化学研究所电分析化学国家重点实验室长春工程学院水利与环境工程学院长春一汽综合利用股份有限公司污水处理厂吉林市碧水源环保科技有限公司

化学需氧量（COD）检测是实现水环境保护与污水处理过程控制的必要措施。本研究将掺杂氟的氧化硒导电玻璃（FTO）/TiO2/PbO2电极与薄层电化学池结合，成功制备了电化学COD传感器用于水体中COD的流动检测。采用电化学分析仪、X-射线光电... 详细信息

化学需氧量（COD）检测是实现水环境保护与污水处理过程控制的必要措施。本研究将掺杂氟的氧化硒导电玻璃（FTO）/TiO2/PbO2电极与薄层电化学池结合，成功制备了电化学COD传感器用于水体中COD的流动检测。采用电化学分析仪、X-射线光电子能谱仪（XPS）、X-射线衍射仪（XRD）对FTO/TiO2/PbO2电极进行表征。结果表明，在传感器工作初期，输出信号强度的快速衰减与电极表面PbSO4的阳极氧化过程有关。优化了PbO2沉积时间和支持电解质Na2SO4浓度，并进行了实际样品的检测。采用此传感器检测湖水水样和河水水样，传感器信号强度变化规律与国标法《水质化学需氧量的测定快速消解分光光度法》（HJ/T 399—2007）一致，并且当湖水水样被高COD值污水水样替代后，传感器信号显著增大。对COD值为30 mg/L的污水水样连续测量45次，平均值为32.5 mg/L，相对标准偏差为6.8%，测试周期为400 s。所研制的电化学COD传感器具有测试周期可调、测试条件温和以及无需使用有毒有害化学试剂等优点，为水体COD常规检测、有机污染物偷排预警以及污水处理过程控制提供了一种有效的绿色解决方案。

关键词：电催化氧化二氧化铅电极化学需氧量化学需氧量传感器羟基自由基

Long-term Trend and Fractal of Annual Runoff Process in Mainstream of Tarim River

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Chinese Geographical Science 2008年第1期18卷 77-84页

作者： XU Jianhua CHEN Yaning LI Weihong dong shan Key Laboratory of Geographic Information Science Ministry of Education Shanghai 200062 China Department of Geography East China Normal University Shanghai 200062 China The Key Laboratory of Oasis Ecology and Desert Environment Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China

Based on the time series data from the Aral hydrological station for the period of 1958-2005,the paper re-veals the long-term trend and fractal of the annual runoff process in the mainstream of the Tarim River by using the wavelet analysis method and the fractal *** main conclusions are as follows:1)From a large time scale point of view,*** time scale of 16(24)years,the annual runoff basically shows a slightly decreasing trend as a whole from 1958 to *** the time scale is reduced to 8(23)or 4(22)years,the annual runoff still displays the basic trend as the large time scale,but it has fluctuated more obviously during the period.2)The correlation dimension for the annual runoff process is 3.4307,non-integral,which indicates that the process has both fractal and chaotic *** correlation dimension is above 3,which means that at least four independent variables are needed to describe the dynamics of the annual runoff process.3)The Hurst exponent for the first period(1958-1973)is 0.5036,which equals 0.5 approximately and indicates that the annual runoff process is in *** Hurst exponents for the second(1974-1989)and third(1990-2005)periods are both greater than 0.50,which indicate that the annual runoff process showed a long-enduring characteristic in the two *** Hurst exponent for the period from 1990 to 2005 indi-cates that the annual runoff will show a slightly increasing trend in the 16 years after 2005.

关键词： annual runoff, wavelet fractal Tarim River

Mitochondrial RNA editing sites affect the phylogenetic reconstruction of gymnosperms

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Plant Diversity 2023年第4期45卷 485-489页

作者： shan-shan dong Xu-Ping Zhou Tao Peng Yang Liu Laboratory of Southern Subtropical Plant Diversity Fairy Lake Botanical GardenShenzhen&Chinese Academy of SciencesShenzhen 518004GuangdongChina School of Life Sciences Guizhou Normal UniversityGuiyang 550001GuizhouChina State Key Laboratory of Agricultural Genomics BGI-ShenzhenShenzhen 518083GuangdongChina

RNA editing is a post-transcriptional process that alters the genetic information of mRNAs,so that the translated proteins deviate from those predicted by the genomic DNA *** editing occurs in a wide range of eukaryotes,including protists,multicellular animals,and land plants(Gray,2012;Ichinose and Sugita,2016).RNA editing in animals,dominated by A-to-I synonymous editing with low editing efficiency(20e30%),might play important roles in the regulation of gene expression(wang et al.,2013).In contrast,RNA editing in plant organelles is usually nonsynonymous,affecting mostly the 2nd and 1st codon positions with very high editing efficiency(~80%).In plants,RNA editing is thought to affect plant phenotype and growth by restoring evolutionarily conserved amino acids and ensuring the correct folding of trans-membrane proteins on the respiratory chain complex(Sloan,2017).

关键词： editing template

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饲料中乙烯雌酚含量的检测方法研究

中国标准化 2024年第10期 200-203页

作者：李东单晓丽周峰安丘市检验检测中心有限公司

本研究旨在开发一种高效、经济的方法,利用高效能液相层析仪(HPLC)配合光二极管侦测器(PDA),对饲料中乙烯雌酚含量进行分析。为了避免在低浓度情况下的误判,同时采用高效液相层析质谱仪(HPLC/MS)进行了再确认。在实验中,饲料样品以甲醇... 详细信息

本研究旨在开发一种高效、经济的方法,利用高效能液相层析仪(HPLC)配合光二极管侦测器(PDA),对饲料中乙烯雌酚含量进行分析。为了避免在低浓度情况下的误判,同时采用高效液相层析质谱仪(HPLC/MS)进行了再确认。在实验中,饲料样品以甲醇为萃取液,经过振荡、离心、浓缩上清液,残渣用70%甲醇溶解,通过Oasis■HLB卡匣去除干扰物质,最后用甲醇进行冲提,冲提液经高效液相层析仪检测。实验结果表明,对于饲料添加0.5、1、3、5 ppm的情况,回收率在80.8%到107.5%。仅采用光二极管侦测器检测时,最低检测限为0.03 ppm;而采用质谱侦测器检测时,最低检测限可达0.005 ppm。研究结果表明,所开发的高效液相层析仪饲料中乙烯雌酚检测方法具有便捷、经济、可行的特点,可作为饲料中乙烯雌酚检验的一种有效方法。

关键词：乙烯雌酚高效能液相层析仪(HPLC) 光二极管侦测器(PDA) 饲料分析液相层析质谱仪(LC/MS)

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A General Law of Precise Asymptotics for Products of Sums under Dependence

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Acta Mathematica Sinica,English Series 2010年第1期26卷 107-116页

作者： Yong ZHANG Xiao Yun YANG Zhi shan dong College of Mathematics Jilin University Changchun 130012 P. R. China

Let {Xn,n ≥ 1} be a strictly stationary LNQD （LPQD） sequence of positive random variables with EX1 = μ 〉 0, and VarX1 = σ^2 〈 ∞. Denote by Sn = ∑i=1^n Xi and γ = σ/μ the coefficients of variation. In this paper, under some suitable conditions, we show that a general law of precise asymptotics for products of sums holds. It can describe the relations among the boundary function, weighted function, convergence rate and limit value in the study of complete convergence.

关键词： general law precise asymptotics products of sums NA (PA) LNQD (LPQD)

SMAC exhibits anti-tumor effects in ECA109 cells by regulating expression of inhibitor of apoptosis protein family

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World Journal of Clinical Cases 2021年第19期9卷 5019-5027页

作者： Ning Jiang Wei-quan Zhang Hong dong Ying-Tao Hao Li-Ming Zhang Lei shan Xiao-dong Yang Chuan-Liang Peng Department of Thoracic Surgery The Second Hospital of Shandong UniversityJinan 250100Shandong ProvinceChina Department of Nursing The Second Hospital of Shandong UniversityJinan 250100Shandong ProvinceChina

BACKGROUND The poor prognosis and rising incidence of esophageal cancer highlight the need for improved therapeutics that are essential prior to ***161 is an SMAC(second mitochondrial activator of caspases)mimic and inhibitor of apoptosis protein(IAP)antagonist which exhibits anti-tumor effects and improves the chemical sensitivity of many *** To ascertain the effects and mechanisms of the SMAC analog LCL161 on esophageal cancer *** MTT assay and TUNEL assay were used to detect cell proliferation and apoptosis,*** blot analysis was used to study the molecular mechanisms of LCL161-induced death of ECA109 *** LCL161 decreased ECA109 cell proliferation in dose-and time-dependent manner and induced apoptosis of ECA109 cells in a dose-dependent ***,LCL161 induced a significant decrease in the expression of the XIAP and significant increase in the expression of *** addition,Bax increased significantly with increasing concentrations of LCL161,and the relative expression of Bax was significantly different between *** These findings support the hypothesis that LCL161 can inhibit proliferation and induce apoptosis in esophageal cancer cells by regulating the expression of IAP family members,suggesting that it has potential to be an effective treatment for esophageal squamous cell carcinoma.

关键词： SMAC Esophageal cancer ECA109 cell Apoptosis protein Inhibitor of apoptosis protein family

Bigflow: A General Optimization Layer for Distributed Computing Frameworks

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Journal of Computer Science & Technology 2020年第2期35卷 453-467页

作者： Yun-Cong Zhang Xiao-Yang wang Cong wang Yao Xu Jian-Wei Zhang Xiao-dong Lin Guang-Yu Sun Gong-Lin Zheng shan-Hui Yin Xian-Jin Ye Li Li Zhan Song dong-dong Miao Baidu Inc. Beijing 100193China Center for Energy-Efficient Computing and Applications Peking UniversityBeijing 100871China

As data volumes grow rapidly, distributed computations are widely employed in data-centers to provide cheap and efficient methods to process large-scale parallel datasets. Various computation models have been proposed to improve the abstraction of distributed datasets and hide the details of parallelism. However, most of them follow the single-layer partitioning method, which limits developers to express a multi-level partitioning operation succinctly. To overcome the problem, we present the NDD (Nested Distributed Dataset) data model. It is a more compact and expressive extension of Spark RDD (Resilient Distributed Dataset), in order to remove the burden on developers to manually write the logic for multi-level partitioning cases. Base on the NDD model, we develop an open-source framework called Bigflow, which serves as an optimization layer over computation engines from most widely used processing frameworks. With the help of Bigflow, some advanced optimization techniques, which may only be applied by experienced programmers manually, are enabled automatically in a distributed data processing job. Currently, Bigflow is processing about 3 PB data volumes daily in the data-centers of Baidu. According to customer experience, it can significantly save code length and improve performance over the intuitive programming style.

关键词： distributed computing programming model optimization technique

Modelling thermodynamics of nanocrystalline binary interstitial alloys

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Journal of Materials Science & Technology 2018年第4期34卷 613-619页

作者： Guibin shan Yuzeng Chen Mingming Gong Hao dong Feng Liu State Key Laboratory of Solidification Processing Northwestern Polytechnical University

Grain boundary （GB） segregation in nanocrystalline alloys can cause reduction of GB energy, which leads to thermodynamic stabilization of nanostructures. This effect has been modelled intensively. However, the previous modelling works were limited to substitutional alloy systems. In this work, thermodynam- ics of nanocrystalline binary interstitial alloy systems was modelled based on a two-sublattice model proposed by Hillert [M. Hillert, et al. Acta Chem. Scand., 24 （1970） 3618] and an atomic configuration for nanocrystalline systems proposed by Trelewicz and Schuh LI.R. Trelewicz, et al. Physical Review B, 79 （2009） 094112]. The modelling calculations agree with the reported experimental data, indicating that the current thermodynamic model is capable of accounting for the alloying effect in the nanocrystalline binary interstitial alloys.

关键词： Nanocrystalline materials Grain boundary segregation Interstitial solid solution Two-sublattice model Thermal stability

Fast-bunching design of compact heavy ion RFQ linac

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Nuclear Science and Techniques 2018年第12期29卷 81-88页

作者： Ke-dong wang You-Jin Yuan Xue-Jun Yin Jian-Cheng Yang heng Du Zhong-shan Li Xiao-Ni Li He Zhao Zi-Qiang dong Jie Liu Jia-Wen Xia Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000 China University of Chinese Academy of Sciences Beijing 100049China Huizhou Research Center of Ion Science Huizhou 516003China

We propose the construction of a compact linac as the injector of a cancer therapy facility at the Institute of Modern Physics(IMP) of the Chinese Academy of Sciences(CAS). Based on a traditional setup, a new compact fast-bunching design is first introduced to optimize the 600 keV/u RFQ with a 0.05 pm A ^(12)C^(4+) beam. This shortens the RFQ structure length from the standard design value of272–230 cm while effectively regulating the particle loss and emittance growth. In addition, a detailed error analysis was performed after the optimization process. The error sources cover input beam parameters errors, machining errors and alignment errors. The simulation results show that the beam loss and emittance growth of the RFQ are acceptable and within typical ranges of error.

关键词：线性加速器设计价值 RFQ 重离子单位面积优化过程中国科学院现代物理