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现代农业科技 2017年第13期 207-210页

作者：王莹张玮史辰刘文军王冠北京市海淀区气象局北京100080

以北京市海淀区新型自动气象站故障排查过程为例,探讨优化自动气象站故障排查方法及后续处理,为新型自动气象站正常运行、探测数据正常采集传输和有效降低自动气象站故障率提供参考。

关键词：新型自动气象站故障排查排查流程北京市海淀区

Engineering atomic Rb-N configurations to tune radical pathways for highly selective photocatalytic H2O2 synthesis coupled with biomass valorization

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Journal of Energy Chemistry 2025年第1期100卷 215-225页

作者： Jiaye Li Shuang Pan Yihuang Chen Qiong liu College of Chemistry and Materials Engineering Wenzhou University Guangdong Provincial Key Laboratory of Chemical Measurement and Emergency Test Technology (China) Institute of Analysis Guangdong Academy of Sciences (China National Analytical CenterGuangzhou)

Photocatalytic oxygen reduction for hydrogen peroxide （H2O2） synthesis presents a green and costeffective production ***,achieving highly selective H2O2synthesis remains challenging,necessitating precise control over free radical reaction pathways and minimizing undesirable oxidative ***,we report for the visible light-driven simultaneous co-photocatalytic reduction of O2to H2O2and oxidation of biomass using the atomic rubidium-nitride modified carbon nitride（CNRb）.The optimized CNRb catalyst demonstrates a record photoreduction rate of 8.01 mM h-1for H2O2generation and photooxidation rate of 3.75 mM h-1for furfuryl alcohol to furoic acid,achieving a remarkable solar-to-chemical conversion （SCC） efficiency of up to 2.27%.Experimental characterizations and DFT calculation disclosed that the introducing atomic Rb–N configurations allows for the high-selective generation of superoxide radicals while suppressing hydroxyl free radical *** is because the Rb–N serves as the new alternative site to perceive a stronger connection position for O2adsorption and reinforce the capability to extract protons,thereby triggering a high selective redox product *** study holds great potential in precisely regulating reactive radical processes at the atomic level,thereby paving the way for efficient synthesis of H2O2coupled with biomass valorization.

关键词： Atomic economy Radical pathway regulation Rubidium atom coordination Biomass valorization

Pomelo biochar as an electron acceptor to modify graphitic carbon nitride for boosting visible-light-driven photocatalytic degradation of tetracycline

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Chinese Journal of Chemical Engineering 2022年第8期35卷 1-11页

作者： Feng Guo Chunli shi wei Sun Yanan liu Xue Lin weilong shi School of Material Science and Engineering Beihua UniversityJilin 132013China School of Energy and Power Jiangsu University of Science and TechnologyZhenjiang 212003China School of Material Science and Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China College of Chemistry Zhengzhou UniversityZhengzhou 450001China

In this study,biochar(BC)derived from pomelo was prepared via a high-temperature calcination method to modify the graphitic carbon nitride(g-C_(3)N_(4))to synthesize the BC/g-C_(3)N_(4)composite for the degradation of the tetracycline(TC)antibiotic under visible light *** experimental results exhibit that the optimal feeding weight ratio of biochar/urea is 0.03:1 in BC/g-C_(3)N_(4)composite could show the best photocatalytic activity with the degradation rate of tetracycline is 83%in 100 min *** improvement of photocatalytic activity is mainly attributed to the following two points:(i)the strong bonding with π-π stacking between BC and g-C_(3)N_(4)make the photogenerated electrons of light-excited g-C_(3)N_(4)transfer to BC,quickly and improve the separation efficiency of carriers;(ii)the introduction of BC reduces the distance for photogenerated electrons to migrate to the surface and increases the specific surface area for providing more active *** study provides a sustainable,economical and promising method for the synthesis of photocatalytic materials their application to wastewater treatment.

关键词： Pomelo Biochar Graphitic carbon nitride Photocatalytic degradation Electron acceptor

A LINEARLY-FITTED CONSERVATIVE （DISSIPATIVE） SCHEME FOR EFFICIENTLY SOLVING CONSERVATIVE （DISSIPATIVE） NONLINEAR WAVE PDES

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Journal of Computational Mathematics 2017年第6期35卷 780-800页

作者： Kai liu XinyuanWu wei shi College of Applied Mathematics Nanjing University of Finance ~ Economics Nanjing 210023 China Department of Mathematics Nanjing University State Key Laboratory for Novel Software Technology at Nanjing University Nanjing 210093 China College of Mathematical Sciences Nanjing Teeh University Nanjing 211816 China

The extended discrete gradient method is an extension of traditional discrete gradient method, which is specially designed to solve oscillatory Hamiltonian systems efficiently while preserving their energy exactly. In this paper, based on the extended discrete gradient method, we present an efficient approach to devising novel schemes for numerically solving conservative （dissipative） nonlinear wave partial differential equations. The new scheme can preserve the energy exactly for conservative wave equations. With a minor remedy to the extended discrete gradient method, the new scheme is applicable to dissipative wave equations. Moreover, it can preserve the dissipation structure for the dissipative wave equation as well. Another important property of the new scheme is that it is linearly-fitted, which guarantees much fast convergence for the fixed-point iteration which is required by an energy-preserving integrator. The efficiency of the new scheme is demonstrated by some numerical examples.

关键词： Conservative (dissipative) wave PDEs Structure-preserving algorithm Linearly-fitted Average Vector Field formula Sine-Gordon equation.

N-(β-氨基-4-氯桂皮酰基)仲丁胺类化合物的合成

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化学学报 1986年第7期44卷 725-728页

作者：彭师奇刘维勤陈素明千金子北京医学院药学系中国科学院化学研究所中国科学院物理研究所北京

刘维勤等曾研究β位取代桂皮酰胺类化合物的抗惊厥活性.为了深入研究β位取代基位阻效应对桂皮酰胺类化合物抗惊厥活性的影响,我们合成了-系列N-(β-氨基-4-氯桂皮酰基)仲丁胺类化合物. 在氢化钠存在下,对氯苯乙酮与碳酸二乙酯缩合,生... 详细信息

刘维勤等曾研究β位取代桂皮酰胺类化合物的抗惊厥活性.为了深入研究β位取代基位阻效应对桂皮酰胺类化合物抗惊厥活性的影响,我们合成了-系列N-(β-氨基-4-氯桂皮酰基)仲丁胺类化合物. 在氢化钠存在下,对氯苯乙酮与碳酸二乙酯缩合,生成对氯苯甲酰基乙酸乙酯.后者经水解、酸化得相应的羧酸.羧酸在室温下用草酰氯进行酰氯化,然后用仲丁胺氨解,得到N-(β-羟基-4-氯桂皮酰基)仲丁胺(3)

关键词：化合物仲丁胺桂皮石油醚溶剂油氨基

原子荧光光谱法测定食品添加剂中砷含量的不确定度评定

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粮油食品科技 2016年第6期24卷 71-75页

作者：梁震陈旻实刘伟王巍武敏建赖佳佳福建出入境检验检疫局技术中心国家消费品安全检测重点实验室福建省检验检疫技术研究重点实验室福建福州350001

依照国家强制性食品安全标准GB 5009.76—2014《食品安全国家标准食品添加剂中砷的测定》,选取食品添加剂泡打粉为样品,从标准溶液溯源,建立测定食品添加剂中砷含量的数学模型。对检测过程中引入的不确定度进行了分类和量化,对各个不确... 详细信息

依照国家强制性食品安全标准GB 5009.76—2014《食品安全国家标准食品添加剂中砷的测定》,选取食品添加剂泡打粉为样品,从标准溶液溯源,建立测定食品添加剂中砷含量的数学模型。对检测过程中引入的不确定度进行了分类和量化,对各个不确定度分量进行了系统全面评定和计算,计算出相应的合成不确定度,给出了测量结果在95%置信区间下的扩展不确定度,建立了双道氢化物发生原子荧光光度仪测定食品添加剂中砷含量的不确定度评定方法。砷含量测试结果表述为1.73±0.24 mg/kg。评定结果表明,不确定度主要来源于标准中间液和校准工作溶液的配制、曲线拟合过程以及重复性测试。

关键词：氢化物原子荧光光谱法食品添加剂砷不确定度

Preparation of porous polyamide 6(PA6)membrane with copper oxide(CuO)nanoparticles selectively localized at the wall of the pores via reactive extrusion

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Nano Materials Science 2022年第2期4卷 169-177页

作者： Tianqi Liang Jie liu Zhaoyang wei Dean shi Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials Ministry-of-Education Key Laboratory for the Green Preparation and Application of Functional MaterialsHubei Key Laboratory of Polymer MaterialsSchool of Materials Science and EngineeringHubei UniversityWuhan430062PR China

In this study,CuO nanoparticles are pre-modified with styrene-maleic anhydride copolymers(SMAs)of different molecular weights and MAH *** the pre-modified CuO nanoparticles(CuO-SMAs)are added to the PA6/SEBS(Styrene Ethylene Butylene Styrene copolymer)(40/60 wt/wt)polymer blends with a co-continuous *** SMA3(MAH=8 wt%,M_(n)=250000 g/mol)is used to modify CuO nanoparticles,and the grafting degree of SMA3 on the surface of CuO reaches 2.74 wt%,90.71%of the added mCuO-SMA3 nanoparticles can be located at the interface of PA6 and SEBS.A porous PA6 membrane with CuO nanoparticles located at the pore walls can be obtained after the SEBS phase is etched with *** catalytic reaction velocity constant(k)for the reduction of p-nitrophenol in NaBH_(4)solutions with the PA6/mCuO-SMA3 porous membrane can reach 1.0040 min^(-1).This work provides a feasible and straightforward method for the preparation of porous polymer membranes with functional nanoparticles located at the wall of the pores.

关键词： Co-continuous CuO nanoparticles Selective distribution Porous PA6 membrane Catalytic performance

Effect of ordered helium bubbles on deformation and fracture behavior of α-Zr

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Journal of Materials Science & Technology 2019年第7期35卷 1466-1472页

作者： Si-Mian liu shi-Hao Li wei-Zhong Han Center for Advancing Materials Performance from the Nanoscale (CAMP-Nano) & Hysitron Applied Research Center in China(HARCC) State Key Laboratory for Mechanical Behavior of Materials Xi’an Jiaotong University

Radiation-induced helium bubbles are detrimental to the mechanical properties of metals, usually causing severe hardening and embrittlement. Hexagonal close-packed(HCP) α-Zr alloys are one of the primary structural materials for nuclear applications, however, the effect of helium bubbles on their deformation and fracture behaviors still remains unexplored. Here, we found that ordered helium bubbles prefer to align along the basal plane in HCP α-Zr. Micro-scale in situ tensile tests revealed that helium bubbles less than 8 nm in size can increase the critical resolved shear stress of the prismatic slip. However, once the helium bubbles are larger than 8 nm, a bubble-softening effect happens due to a decrease in number density of helium bubbles and an increase in porosity. Once the Schmid factor of basal slip is considerably higher than prismatic slip, bubble coalescence along the basal plane becomes the major failure mode in helium-irradiated α-Zr.

关键词： α-Zr Helium bubbles Prismatic slip Coalescence Fracture

Fast Evaluation of Aberration-Induced Intensity Distribution in Partially Coherent Imaging Systems by Cross Triple Correlation

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Chinese Physics Letters 2011年第10期28卷 119-122页

作者： liu shi-Yuan liu wei WU Xiao-Fei Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan 430074 State Key Laboratory of Digital Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430074

We propose a method suitable for the fast calculation and evaluation of aberration-induced intensity distribution in partially coherent imaging systems,such as projection lithographic *** method is based on transmission cross coefficient(TCC)decomposition by a general operator,namely cross triple correlation(CTC).By expanding the aberrated pupil function into a Taylor series,the TCC is decomposed into different *** term is further represented as a weighted sum of several *** exploring the properties of CTC,the aerial image intensity induced by wavefront aberration is calculated quickly and separated clearly from that without *** results and discussion are presented.

关键词： Intensity aberration expanding

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医学院低年级学生自我认同感的调查研究

保健医学研究与实践 2015年第6期12卷 4-7页

作者：刘宇丹石流伟徐清龙曾晓宇李飞川北医学院预防医学系中国人民解放军77680部队30分队财务科

目的了解医学院低年级学生自我认同感的现状。方法采用奥克斯(Ochse)和普拉格(Plug)编制的自我认同感量表,以随机分层整群抽样的方法抽取某医学院大一和大二430名学生进行不记名式问卷调查。结果 282名(65.6%)学生自我认同感水平较低,73... 详细信息

目的了解医学院低年级学生自我认同感的现状。方法采用奥克斯(Ochse)和普拉格(Plug)编制的自我认同感量表,以随机分层整群抽样的方法抽取某医学院大一和大二430名学生进行不记名式问卷调查。结果 282名(65.6%)学生自我认同感水平较低,73名(17.0%)学生自我认同感处于平均水平,75名(17.4%)学生自我认同感水平较高。男生和女生之间自我认同感的差异无统计学意义(P=0.260);农村和城镇学生之间的自我认同感差异无统计学意义(P=0.867);大一和大二学生之间自我认同感差异有统计学意义(P=0.001);医学类和非医学类学生之间的自我认同感差异有统计学意义(P=0.002);独生子女和非独生子女之间的自我认同感差异有统计学意义(P=0.004);学习成绩和自我认同感之间存在关联(P=0.011)。结论医学院低年级大部分学生还处于自我认同感的形成当中,而且他们的自我认同感在年级、专业和是否是独生子女之间存在差异,表现为大二学生高于大一学生,医学类专业学生高于非医学类专业,独生子女高于非独生子女。此外,学习成绩和自我认同感之间有关联,即自我认同感水平越高的学生学习成绩越好。

关键词：大学生医学生自我认同感