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A time-dependent luminescent phosphor of Na_(2)Ba_(2)Si_(2)O_(7):Eu for multi-level encryption and dynamic information display

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Journal of Advanced Ceramics 2024年第4期13卷 429-436页

作者： Jie Shao Xiyang Li Meng Liu Haiqin sun Qiwei Zhang dengfeng Peng Fuchi Liu College of Physics and Technology Guangxi Normal UniversityGuilin 541004China Guangxi Key Laboratory of Nuclear Physics and Technology Guangxi Normal UniversityGuilin 541004China Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province College of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhen 518060China

Photo-stimuli responsive materials show great potential in the fields of information encryption and storage due to their distinctive spatial or temporal color ***,the conventional single or multi-color static outputs by light stimulus difficulty meet practical requirements for high-security optical storage ***,a novel dynamic irradiation-responsive phosphor of Na_(2)Ba_(2)Si_(2)O_(7):Eu is demonstrated,exhibiting high storage stability and convenient readout *** inherent Eu^(2+)luminescence can be dynamically tuned,instantly read out,and conveniently erased by controlling irradiation duration of a portable diode laser(365 nm).The modulation mechanism is unraveled by optically induced oxidation reactions of Eu^(2+)→Eu^(3+)and defects as killer *** excellent luminescence modulation degree(ΔR_(t)=89.5%)and the accompanying larger color contrast enable the creation of invisible optical codes with multi-level encryption in bright or dark *** results indicate potential applications of Na_(2)Ba_(2)Si_(2)O_(7):-based materials in information encryption and invisible optical storage,and are expected to expand more investigations on optically induced PL modulation behaviors based on mixed valences and defects.

关键词： light irradiation luminescent modulation invisible optical storage

Atlas Based Kinematic Optimum Design of the Stewart Parallel Manipulator

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Chinese Journal of Mechanical Engineering 2015年第1期28卷 20-28页

作者： SHAO Zhufeng TANG Xiaoqiang WANG Liping sun dengfeng State Key Laboratory of Tribology Department of Mechanical EngineeringTsinghua University Beijing Key Lab of Precision/Ultra-precision Manufacturing Equipments and Control Tsinghua University School of Aeronautics and Astronautics Engineering Purdue University

Optimum design is a key approach to make full use of potential advantages of a parallel manipulator. The optimum design of multi-parameter parallel manipulators（more than three design parameters）, such as Stewart manipulator, relies on analysis based and algorithm based optimum design methods, which fall to be accurate or intuitive. To solve this problem and achieve both accurate and intuition, atlas based optimum design of a general Stewart parallel manipulator is established, with rational selection of design parameters. Based on the defined spherical usable workspace（SUW）, primary kinematic performance indices of the Stewart manipulator involving workspace and condition number are introduced and analyzed. Then, corresponding performance atlases are drawn with the established non-dimensional design space, and impact of joint distribution angles on the manipulator performance is analyzed and illustrated. At last, an example on atlas based optimum design of the Stewart manipulator is accomplished to illustrate the optimum design process, considering the end-effector posture. Deduced atlases can be flexibly applied to both quantitative and qualitative analysis to get the desired optimal design for the Stewart manipulator with respect to related performance requirements. Besides, the established optimum design method can be further applied to other multi-parameter parallel manipulators.

关键词： optimum design performance atlas parallel mechanism Stewart

Causal relationship between circulating vitamin C and 25-hydroxyvitamin D concentrations and common mental disorders-a Mendelian randomization study

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Food Science and Human Wellness 2024年第4期13卷 1877-1885页

作者： Yuanyuan Wang Lirong Dong Meng Zhao Shiyu Yin Pan Da dengfeng Xu Yifei Lu Jiayue Xia Niannian Wang Shaokang Wang Guiju sun Key Laboratory of Environmental Medicine and Engineering of Ministry of Education and Department of Nutrition and Food HygieneSchool of Public HealthSoutheast UniversityNanjing 210009China Department of Integrated Service and Management Jiangsu Provincial Center for Disease Control and PreventionNanjing 210009China

Mental disorders seriously affect people’s health and social *** Mendelian randomization(MR)study was designed to investigate the causal relationship between circulating vitamin C(VC)or 25-hydroxyvitamin D(25(OH)D)levels and mental *** data used for the MR analysis were derived from the summary genome-wide association studies(GWAS)database for VC and 25(OH)D and from the Finn Gen consortium for fourteen mental *** on the inverse variance weighted(IVW)method,we found a potential causal association between circulating VC and anxiety disorders(IVW:OR=1.139,95%CI:1.023-1.269,P=0.018).However,no causal association was found between VC or 25(OH)D and other mental disorders(P>0.05).In the reverse MR analysis,individuals with Alzheimer’s disease was causally associated with higher concentrations of circulating VC(P=0.012),while individuals with anxiety disorders had a negative association between the concentrations of 25(OH)D(P=0.012).However,the current evidence does not support a causal relationship between VC or 25(OH)D and other mental *** addition,there was no causal association between circulating VC and 25(OH)D(P>0.05).Future studies are needed to confirm these findings and to elucidate the mechanisms of potential causality.

关键词： Circulating vitamin C 25-Hydroxyvitamin D Mental disorder Mendelian randomization

BINARY SEQUENCE WITH PERFECT SPREADING STAIRCASE PROFILE OF LINEAR COMPLEXITY

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Systems Science and Mathematical Sciences 1997年第1期10卷 75-79页

作者： YANG Yi-clan sun dengfeng (Department of Information Engineering, Beijing University of Posts & Telecommunications, Be iiing 100088 China)

This paper makes the following investigations.1. To solve the second open problem proposed by *** and ***[1];2. To prove the nonexistence of PSSP sequence with the smallest(or biggest) density;3. To find the PSSP sequence with (complementary) Hamming weight m for every positive integer m;4. To propose a generalization form of the known IYM sequence.

关键词： Linear complexity pseudo-random sequence colltinued fraction cryptography

Effects of oat β-glucan–based prebiotic blended formulas on defecation and gut microbiota in Chinese adults: a randomized clinical trial

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Food Science and Human Wellness 2024年

作者： Aiqi Li Lei Jin Hui Xia Meiyuan Feng Xirui Zhou Yifang Chu Feng Liu Lanxing Jia Ximin Chen dengfeng Xu Shanjie Ma Xiaofan Xu Xinyu Wang Xiaoqing Li Guiju sun Liegang Liu Key Laboratory of Environmental Medicine and Engineering of Ministry of Education， and Department of Nutrition and Food Hygiene， School of Public Health Southeast University Department of Nutrition and Food Hygiene， Hubei Key Laboratory of Food Nutrition and Safety， School of Public Health， Tongji Medical College， Huazhong University of Science and Technology Department of R&D Life Science，PepsiCo Inc Nutrition and Healthy Food Committee of Chinese Nutrition Society Health Management Branch of Chinese Nutrition Society

Digestive health is important for overall well-being， but gut health problems are common in the Chinese population. The objective of this study was to investigate the effects of oat β-glucan–based prebiotic blended formulas in humans on digestive health by assessing defecation frequen-cy， defecation symptoms， stool quality， self-reported digestive feelings， defecation satisfaction， and gut bacteria. A parallel， randomized， double-blind， controlled trial was conducted in 168 eli-gible adults randomized to three groups for 14 days: Intervention Groups A and B received two different doses of oat β-glucan–based prebiotic blended formulas and a Control Group received oat β-glucan mixed with hydroxypropylmethyl-cellulose and microcrystalline cellulose. Partici-pants completed a defecation diary and Bristol stool chart daily and digestive system question-naires weekly. Fecal samples were collected on Day 0 and Day 14 to evaluate gut bacteria using 16S rDNA analysis. Both formulas improved defecation frequency， stool quality， defecation symptoms， defecation satisfaction， and on digestive health of human， compared with baseline (P < 0.05). Both formulas led to increased quantities of Bifidobacterium and Akkermansia bacteria， compared to control， on Day 14. This study therefore demonstrated the beneficial effects of oat β-glucan–based prebiotic blended formulas on gut health in generally healthy Chinese adults. These formulas are a feasible nutritional strategy for digestive health.

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熊耳山矿集区小河流域水体及底泥重金属污染评价

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矿产综合利用 2024年第1期45卷 109-119页

作者：张登峰孙建伟中国地质调查局西安矿产资源调查中心陕西西安710100

这是一篇矿山环境领域的论文。河流是矿产资源开发过程中产生的重金属最主要的迁移途径和汇聚地,熊耳山矿集区矿产资源开发对河流的影响程度尚不清晰。为准确掌握熊耳山矿集区矿产资源开发对河流重金属的影响,以矿集区内小河流域的水体... 详细信息

这是一篇矿山环境领域的论文。河流是矿产资源开发过程中产生的重金属最主要的迁移途径和汇聚地,熊耳山矿集区矿产资源开发对河流的影响程度尚不清晰。为准确掌握熊耳山矿集区矿产资源开发对河流重金属的影响,以矿集区内小河流域的水体和底泥为研究对象,分析了小河干流及其主要支流水体和底泥中Cu、Pb、Zn、Cd、As、Hg重金属含量特征。用单项污染指数和内梅罗综合污染指数法对水体重金属污染程度进行评价;用地质累积指数法和质量基准法对河流底泥中重金属累积程度和污染程度进行评价。结果表明,小河流域水体中6种重金属平均含量在0.08~289.86μg/L之间,污染程度As>Hg>Cd>Pb>Cu>Zn,主要重金属污染物为As、Hg,主要污染河段分布于矿业活动强烈区,矿产资源开发是引起河流水体污染的主要因素。Cu、Pb、Zn、Cd、As、Hg在小河流域河道底泥中累积效应显著,重金属污染程度严重,质量基准法评价结果显示,小河流域底泥中Pb、Cd、Cu、Zn、As、Hg所有样品均严重污染,综合地质累积指数法和质量基准法评价结果,小河流域河道底泥污染程度:Pb>Cd>Cu>Zn>As>Hg,其中Pb、Zn、Cu、Cd是主要污染元素,Hg,As是次要污染元素。研究认为:熊耳山矿集区矿产资源开发是引起小河流域水体、河道底泥重金属污染的主要因素,已经对河流水体和底泥造成不同程度的重金属污染,加强矿产资源开发全过程的源头治理和监管,是保护和改善小河流域重金属污染的根本手段。

关键词：矿山环境水体底泥重金属污染

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基于三自由度液压小车的总段低应力调姿技术

机械与电子 2023年第9期41卷 57-62页

作者：孙登峰齐峰张伟军上海交通大学机械与动力工程学院上海200240 江南造船厂精度管理部上海201913

针对液压小车在执行部分指令时球头可能会发生滑移,且现场制定的调姿指令存在局部受力不合理的问题,设计一套具备三自由度油缸协同运动能力的液压系统。对常见调姿工况进行了有限元分析,在此基础上提出保证总段低应力状态的调姿指令计... 详细信息

针对液压小车在执行部分指令时球头可能会发生滑移,且现场制定的调姿指令存在局部受力不合理的问题,设计一套具备三自由度油缸协同运动能力的液压系统。对常见调姿工况进行了有限元分析,在此基础上提出保证总段低应力状态的调姿指令计算准则及具体计算方法,最终通过实验验证了该液压系统和相应调姿控制算法的可行性。

关键词：总段调姿液压系统低应力控制运动规划

急性心肌梗死患者红细胞比容、脂蛋白(a)及平均血小板体积对PCI术后主要不良心血管事件的预测效能

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河南医学研究 2022年第18期31卷 3376-3379页

作者：孙登峰白广海张静濮阳县人民医院心血管内科河南濮阳457002 濮阳油田总医院心血管内科河南濮阳457001

目的研究急性心肌梗死(AMI)患者红细胞比容(Hct)、脂蛋白(a)[LP(a)]、平均血小板体积(MPV)对经皮冠状动脉介入(PCI)术后主要不良心血管事件(MACE)风险的预测效能。方法选取2019年2月至2021年10月于濮阳县人民医院接受PCI治疗的221例AMI... 详细信息

目的研究急性心肌梗死(AMI)患者红细胞比容(Hct)、脂蛋白(a)[LP(a)]、平均血小板体积(MPV)对经皮冠状动脉介入(PCI)术后主要不良心血管事件(MACE)风险的预测效能。方法选取2019年2月至2021年10月于濮阳县人民医院接受PCI治疗的221例AMI患者。随访6个月,根据其预后情况分为MACE组(64例)、未MACE组(157例)。比较两组体质量指数(BMI)、左室射血分数(LVEF)、血脂相关指标、血小板参数等基线资料。分析AMI患者PCI术后发生MACE的影响因素,通过受试者工作特征(ROC)曲线和曲线下面积(AUC)分析血清相关细胞因子水平联合检测对AMI患者发生MACE的预测价值。结果两组LP(a)、Hct、MPV比较,差异有统计学意义(P0.05)。多因素logistic回归分析显示,LP(a)≥310.95 mg·L^(-1)、MPV≥8.55 fL是AMI患者发生MACE的危险因素,Hct≥36.23%是AMI患者发生MACE的保护因素(P<0.05)。ROC曲线分析结果显示Hct、LP(a)、MPV联合预测AMI患者发生MACE的AUC值为0.908,敏感度为92.19%、特异度为92.99%(P<0.05)。结论Hct、LP(a)、MPV表达水平与AMI患者PCI术后MACE有关,联合检测对MACE的预测效能较高,可为预后评估、改善提供合理依据,预防MACE发生。

关键词：急性心肌梗死红细胞比容脂蛋白(a) 平均血小板体积主要不良心血管事件

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自全式无线霍尔电流传感器

仪器仪表学报 2014年第8期35卷 1700-1706页

作者：文玉梅孙登峰李平张俊张自强重庆大学光电工程学院传感器及仪器研究中心重庆400030

输/供电线的电流、温度等是电网运行和用电安全监测的重要参数，需要沿电网和伴随用电设备广泛监测。无线传感器是监测的首选，但是无线传感器的电池维护或者外接电源，限制了无线传感器应用。设计了一种自全式无线霍尔电流传感器，在... 详细信息

输/供电线的电流、温度等是电网运行和用电安全监测的重要参数，需要沿电网和伴随用电设备广泛监测。无线传感器是监测的首选，但是无线传感器的电池维护或者外接电源，限制了无线传感器应用。设计了一种自全式无线霍尔电流传感器，在同一磁路上实现传感和能量采集，利用霍尔元件传感电流，用线圈采集磁场能量为传感及数据无线发射提供电源。使用时传感器只需扣在被监测电线外包层，无需外接电源并免除电池维护，就可以持久实现无线传感。实验表明：该无线传感器的灵敏度达15．10 mV/A，可自主实现2～100 A的电流检测和无线数据传输。

关键词：电流传感器能量采集自供电无线传感霍尔元件