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QuECheRS结合HPLC检测辣椒及其制品中天然辣椒素、二氢辣椒素和合成辣椒素

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食品科学 2025年第2期46卷 240-247页

作者：成璐瑶温雅君石文婷周子莹马丽艳中国农业大学食品科学与营养工程学院北京100083 北京市农产品质量安全中心北京100029 农业农村部农产品质量检验测试中心(北京) 北京100083

建立一种QuECheRS结合高效液相色谱快速检测辣椒及其制品中的天然辣椒素、二氢辣椒素和合成辣椒素的方法。样品用乙腈提取,无水硫酸镁、十八烷基硅烷(C18)、乙二胺-N-丙基硅烷化硅胶、石墨化炭黑复合吸附剂净化。采用Agilent Eclipse Pl... 详细信息

建立一种QuECheRS结合高效液相色谱快速检测辣椒及其制品中的天然辣椒素、二氢辣椒素和合成辣椒素的方法。样品用乙腈提取,无水硫酸镁、十八烷基硅烷(C18)、乙二胺-N-丙基硅烷化硅胶、石墨化炭黑复合吸附剂净化。采用Agilent Eclipse Plus C18(150 mm×4.6 mm,5μm)分离,以0.4%磷酸水溶液和90%乙腈溶液为流动相进行梯度洗脱,荧光检测器进行检测。结果表明:天然辣椒素、二氢辣椒素和合成辣椒素在0.20~100 mg/L范围内线性关系良好,决定系数(R2)均大于0.999。天然辣椒素的方法检出限为0.014~0.069 mg/kg,定量限为0.046~0.23 mg/kg;二氢辣椒素的方法检出限为0.023~0.12 mg/kg,定量限为0.077~0.39 mg/kg;合成辣椒素的方法检出限为0.018~0.088 mg/kg,定量限为0.059~0.30 mg/kg。在干辣椒、鲜辣椒、香菇酱、辣椒油4种基质中,3个不同添加水平下的加标回收率为91.6%~117.2%,相对标准偏差为0.2%~6.1%。该方法简便、准确,不仅适用于干、鲜辣椒,而且适用于高油、高蛋白等辣椒制品中天然辣椒素、二氢辣椒素和合成辣椒素含量的检测。

关键词： QuECheRS 高效液相色谱辣椒辣椒素合成辣椒素

Cytochrome P450 monooxygenase specific activity reduction in wheat Triticum aestivum induced by soil roxithromycin stress

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Frontiers of Environmental Science & Engineering 2016年第2期10卷 270-275页

作者： Kangxin he Qixing zhou MOE Key Laboratory of Pollution Processes and Environmental Criteria/Tianjin Engineering Center of Environmental Diagnosis and Contamination Remediation College of Environmental Science and Engineering Nankai University Tianjin 300071 China

Roxithromycin, livestock growth promoter, as widely used medicine and arouses concern because its occurrence and persistence in soil environments. However, effects of roxithromycin in higher plants are still vague. Accordingly, we hypothesized that roxithromycin-con- taminated soil may exhibits ecotoxicological effects in wheat （Triticum aestivum）. In this study, effects induced by a gradient concentration of roxithromycin stress （0.01, 0.1, 1, 10, and 100 ***-1） was investigated in a 7-d soil test in T. aestivum. Results indicated that the specific activity of cytochrome P450 （CYP450） monooxygenase was decreased dramatically with the concentration of roxithro- mycin in soil. The IC50 value was ***-1 of roxithromycin. On the contrary, the growth related endpoints （i.e., the germination percentage, the biomass and the height）, the content related endpoints （i.e., soluble protein content and CYP450 content）, and the superoxide dismutase （SOD） activity failed to reveal the roxithromy- cin-induced effects. Further analysis revealed that the CYP450 monooxygenase specific activity reduction was enzymatic mechanism mediated, other than oxidative stress induced. We conclude that the soil roxithromycin declined the CYP450 monooxygenase activity in T. aestivum by the inhibition of the enzymatic mechanism. Further efforts can include, but are not limited to, investigation of joint effects induced by combined exposure of roxithromycin and the pesticides and evalua- tion of the similar effects in other higher plants.

关键词： roxithromycin toxic effect cytochrome P450monooxygenase soil environment Triticum aestivum,biomarker

health Economic Assessment for Screening of Gastric Cancer in AHigh Risk Population in Northeastern China

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Chinese Journal of Cancer Research 2011年第1期23卷 21-24页

作者： Ling zhou Peng Guan Li-ping Sun Qin-cheng he Yuan Yuan Bao-sen zhou Department of Epidemiology School of Public HealthShenyang 110001 China Cancer Institute First Affiliated Hospital China Medical UniversityShenyang 110001 China

Objective：To assess economic cost-effects for the screening programs of gastric cancer in a high risk population in northeastern ***：The data were collected from November 2001 to December *** multi-stage sampling to define the screening group and the control group was applied in this *** stage screening programs were used in the *** epidemiological survey and serum PG test were carried out in the first *** endoscopy and pathological examination were performed in the second stage *** was assessed by the increased quality adjusted life-year（QALY） because of reduced gastric cancer deaths in ***：A total of 27,970 participants（n=7,128 screening group,n=20,842 control group） were enrolled in the *** nine gastric cancer cases were detected in the screening group with 20 cases in the early stage and 9 cases in the advanced stage,*** six gastric cancer cases were detected in the control group,all of whom were in the advanced stage and had died before the study *** screening and treatment of 29 cases cost $152,227 and $5,249 per each case,*** costs were $459 to gain per ***：The screening program of gastric cancer used in our study is an economic and society-beneficial measure to detect gastric cancer in high risk *** methods fit China＇s present economic development level.

关键词： Gastric cancer Screening Economics

Honeycomb-like biochar framework coupled with Fe_(3)O_(4)/FeS nanoparticles as efficient heterogeneous Fenton catalyst for phenol degradation

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Journal of Environmental Sciences 2024年第2期136卷 390-399页

作者： Aihua cheng Yi he Xiaohe Liu Chi he Department of Environmental Engineering College of Geology and EnvironmentXi’an University of Science and TechnologyXi’an 710054China State Key Laboratory of Multiphase Flow in Power Engineering School of Energy and Power EngineeringXi’an Jiaotong UniversityXi’an 710049China National Engineering Laboratory for VOCs Pollution Control Material and Technology University of Chinese Academy of SciencesBeijing 101408China

Achieving an efficient and stable heterogeneous Fenton reaction over a wide pH range is of great significance for wastewater ***,a pollen-derived biochar catalyst with a unique honeycomb-like structure,coupled with the dispersion of magnetic Fe_(3)O_(4)/FeS(Fe/S)nanoparticles,was synthesized by simple impregnation precursor,followed by *** prepared Fe/S-biochar catalyst demonstrated outstanding phenol degradation efficiency across a wide pH range,with 98%of which eliminated even under neutral conditions(pH 7.0).The high catalytic activity was due to the multilevel porous structure of pollenderived biochar provided enough active sites and allowed for better electron transfer,then increases oxidation ability to promote the ***,the acid microenvironment formed by SO_(4)^(2-)group from Fe/S composite extended the pH range for Fenton reaction,and S^(2-)facilitated the conversion of≡Fe^(3+)to≡Fe^(2+),resulting in remarkable degradation ***,biochar can effectively promote cycling stability by limiting Fe *** work may provide a general strategy for designing 3D framework biochar-based Fe/S catalysts with excellent performance for heterogeneous Fenton reactions.

关键词： Biomass Biochar Fenton reaction Fe_(3)O_(4)/FeS(Fe/S) Phenol degradation

Retrieval of Angle-Dependent Strong-Field Ionization by Using High Harmonics Generated from Aligned N_(2) Molecules

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Chinese Physics Letters 2021年第12期38卷 13-20页

作者： Xiaoli Guo cheng Jin Ziqiang he Song-Feng Zhao Xiao-Xin zhou Ya cheng State Key Laboratory of Precision Spectroscopy East China Normal UniversityShanghai 200062China Department of Applied Physics Nanjing University of Science and TechnologyNanjing 210094China College of Physics and Electronic Engineering Northwest Normal UniversityLanzhou 730070China Beijing National Laboratory for Condensed Matter Physics and Institute of PhysicsChinese Academy of SciencesBeijing 100190China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China Collaborative Innovation Center of Light Manipulations and Applications Shandong Normal UniversityJinan 250358China

We propose a method to retrieve the angle-dependent strong-field ionization of highest occupied molecular orbital(HOMO)from high-order harmonic generation(HHG)of aligned *** method is based on the single-molecule quantitative rescattering model with known alignment distribution and photo-recombination cross sections of fixed-in-space *** the macroscopic HHG of aligned N2 molecules,we show that angledependent ionization of HOMO can be successfully retrieved at both low and high degrees of *** then show that the error in the retrieved angular dependence of ionization becomes larger if the uncertainty in the alignment distribution is introduced in the retrieval *** also examine that the retrieved ionization of HOMO is much deviated from the accurate one if the intensity of probe laser becomes higher such that inner HOMO-1 can contribute to HHG.

关键词： alignment Harmonic harmonic

Seasonal variation of gut Cyanophyta contents and liver GST expression of mud carp(Cirrhina molitorella) and Nile tilapia(Oreochromis niloticus) in the tropical Xiangang Reservoir(Huizhou,China)

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Chinese Science Bulletin 2012年第6期57卷 615-622页

作者： cheng WeiXuan LIANG XuFang SheN Dan zhou Qiong he Yan he Shan LI GuangYu College of Fisheries Huazhong Agricultural UniversityWuhan 430070China

Liver glutathione S-transferase(GST) plays a major role in the detoxification of microcystins(MCs) via conjugation to glutathione(GSH).We evaluated the relationship between seasonal variation in fish gut contents and the expression of GST isoforms in mud carp(Cirrhina molitorella) and Nile tilapia(Oreochromis niloticus).We quantified the abundance and diversity of plankton in the water column and foregut of mud carp and Nile tilapia in the tropical Xiangang Reservoir between October 2007 and July *** mRNA expression of 7 liver GST isoforms was determined by real-time *** gut contents of both species were dependent on the amount and type of phytoplankton and zooplankton in the *** expression of liver GST genes in Nile tilapia and mud carp was positively and negatively correlated,respectively,with the abundance of toxic cyanobacteria in the *** expression of liver GST mRNA was correlated to the abundance of toxic cyanobacteria in the gut contents of both species,suggesting that mRNA expression of GST isoforms could be used as a biomarker in Nile tilapia and mud carp to monitor cyanobacteria blooms in reservoirs.

关键词：尼罗罗非鱼蓝藻水华肠内容物鲮鱼水库季节变化热带谷胱甘肽S

Real-time reconfigurable metasurfaces enabling agile terahertz wave front manipulation

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Light(Science & Applications) 2023年第12期12卷 2551-2553页

作者： Huixian zhou cheng Zhang School of Optical and Electronic Information&Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan 430074China

Real-time controlled programmable metasurfaces,having an array-of-subarrays architecture under the control of one-bit digital coding sequence,are demonstrated for rapid and precise multifunctional Terahertz wave front... 详细信息

关键词： reconfigurable wave arrays

A VARIATIONAL EXPECTATION-MAXIMIZATION METHOD FOR The INVERSE BLACK BODY RADIATION PROBLEM

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Journal of Computational Mathematics 2008年第6期26卷 876-890页

作者： Jiantao cheng Tie zhou School of Mathematical Sciences Peking University Beijing 100871 China

The inverse black body radiation problem, which is to reconstruct the area temperature distribution from the measurement of power spectrum distribution, is a well-known ill-posed problem. In this paper, a variational expectation-maximization （EM） method is developed and its convergence is studied. Numerical experiments demonstrate that the variational EM method is more efficient and accurate than the traditional methods, including the Tikhonov regularization method, the Landweber method and the conjugate gradient method.

关键词： Inverse black body radiation problem Variational EM method.

Reaction Torque Control of Redundant Free-floating Space Robot

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International Journal of Automation and computing 2017年第3期14卷 295-306页

作者： Ming-he Jin cheng zhou Ye-Chao Liu Zi-Qi Liu Hong Liu State Key Laboratory of Robotics and System Harbin Institute of Technology Harbin 150001 China

This paper presents the reaction torque based satellite base reactionless control or base disturbance minimization of a redundant free-floating space robot. This subject is of vital importance in the study of the free-floating space robot because the base disturbance minimization will result in less energy consumption and prolonged control application. The analytical formulation of the reaction torque is derived in this article, and the reaction torque control can achieve reactionless control and satellite base disturbance minimization. Furthermore, we derive the reaction torque based control of the space robot for base disturbance minimization from both the non-strict task priority and strict task priority control strategy. The dynamics singularity in the proposed algorithm is avoided in this paper. Besides, a real time simulation system of the space robot under Linux/real time application interface（RTAI） is developed to verify and test the feasibility and reliability of the method. The experimental results demonstrate the feasibility of online reaction torque control of the redundant free-floating space robot.

关键词： Redundant space robot reaction torque reactionless control base disturbance minimization Linux/real time application interface(RTAI)