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Chinese Chemical Letters 2013年第4期24卷 347-350页

作者： Li Huang Jun-pei Chen Can Jin Wei-Ke Su Key Laboratory for Green Pharmaceutical Technologies and Related Equipment of Ministry of Education College of Pharmaceutical SciencesZhejiang University of Technology

A series of substituted 2,3-diaryl-2-azabicyclo[2.2.2]octan-5-ones have been prepared by an efficient three-component aza-Diels-Alder cycloaddition reaction in water catalyzed by layered α-zirconium hydrogen phosphate （α-ZrP） and sodium calix[4]arene sulfonates bearing pendant short aliphatic chains. The 18 synthesized compounds were assayed for acetylcholinesterase inhibition using mouse acetvlcho]inesterase.

关键词： Aza-Diels-Alder cycloadditionAzabicyclo[2.2.2 ]octan-5-oneSodium calixarene sulfonate α-ZrPAChE inhibition

我国9省铁皮石斛食用情况及消费人群4种常见重金属累积暴露评估研究

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中国食品卫生杂志 2024年第1期36卷 39-48页

作者：黄雅琳包汇慧邱雪娇李建文张磊张首楠李琦曹佩覃思湖南农业大学湖南长沙410125 国家食品安全风险评估中心北京100022

目的了解我国9省居民铁皮石斛食用情况,评估铁皮石斛消费人群铅(Pb)、镉(Cd)、汞(Hg)、砷(As)4种重金属的累积暴露量和潜在的健康风险。方法基于2019年和2022年中国9省居民铁皮石斛消费量数据和文献筛选得到的部分地区铁皮石斛4种重金... 详细信息

目的了解我国9省居民铁皮石斛食用情况,评估铁皮石斛消费人群铅(Pb)、镉(Cd)、汞(Hg)、砷(As)4种重金属的累积暴露量和潜在的健康风险。方法基于2019年和2022年中国9省居民铁皮石斛消费量数据和文献筛选得到的部分地区铁皮石斛4种重金属含量数据,采用简单分布模型计算4种重金属暴露量,评估其健康风险;并在此基础上利用危害指数法(HI)进行累积暴露评估。结果铁皮石斛消费者主要以食用干品为主(37.3%),其中以泡饮方式食用较多,单次消费量的平均值为8.2 g/人;铁皮石斛鲜品食用人群占总调查人数的12.9%,以榨汁为主,单次消费量的平均值为30.8 g/人。暴露评估结果显示,在铁皮石斛(干/鲜)4种重金属暴露量中,干品均高于鲜品且Pb的平均暴露水平(干/鲜)最高;以健康指导值或基准剂量的5%进行判定,在铁皮石斛干品中不同性别-年龄组消费者As、Pb的平均暴露量的暴露边界值(MOE)>1;Pb P95暴露量的MOE值<1;Cd和Hg暴露量均低于其健康指导值的5%。不同省份居民铁皮石斛重金属暴露评估结果表明,江西省铁皮石斛消费居民4种重金属暴露量均最高。江西和浙江两省Pb的高端暴露量的MOE值<1。4种元素累积评估显示铁皮石斛消费者的HI值均<1。结论我国9省铁皮石斛消费者As、Cd、Hg暴露的健康风险较低,高食物量消费人群应关注铅暴露的健康风险。

关键词：铁皮石斛重金属食品污染物暴露评估累积风险评估

基于Budyko假设的清水河和白河流域径流变化及其影响因素分析

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水土保持通报 2024年第3期44卷 56-64页

作者：李赟李博睿张益闽王伟张良张飘裴宏伟河北建筑工程学院河北张家口075000 河北省水质工程与水资源综合利用重点实验室河北张家口075000 河北省张家口水文勘测研究中心河北张家口075000 北京大学城市与环境学院北京100871

[目的]综合分析清水河流域和白河流域的年径流变化及其主导因素,进一步揭示永定河流域和潮白河流域实际径流的变化及其影响因素,旨在为张家口地区水资源规划与管理提供理论依据。[方法]基于Budyko模型以永定河上游的清水河流域和潮白河... 详细信息

[目的]综合分析清水河流域和白河流域的年径流变化及其主导因素,进一步揭示永定河流域和潮白河流域实际径流的变化及其影响因素,旨在为张家口地区水资源规划与管理提供理论依据。[方法]基于Budyko模型以永定河上游的清水河流域和潮白河上游的白河流域为研究对象构建流域水热耦合平衡方程,精确计算潜在蒸散发对主要气象因子的敏感系数,再通过敏感系数计算径流对主要气象因子的弹性系数,进一步计算气候变化和人类活动对径流变化的贡献率。[结果](1)近年来清水河流域和白河流域各气象因子的弹性系数呈现增加的趋势,这种趋势揭示了这两个流域日益增强的气候—水文耦合关系。和白河流域相比,清水河流域的水文过程对气候变化更加敏感。(2)人类活动对清水河流域和白河流域的径流量变化起主导作用。清水河流域和白河流域人类活动对径流变化的影响率分别是65.37%和83.90%。(3)较之于Fu,Choudhury-Yang和Wang-Tang公式,Zhang公式在清水河流域和白河流域具有更好的适用性,能较好地模拟流域的实际蒸散发量,R~2达到0.97。[结论]人类活动对研究区径流变化的影响率为65.37%~83.90%,气候因素的影响率为16.10%~34.63%,今后应同时考虑气候和人类活动的影响,继续加强水分限制区的径流蒸散过程机理研究,以保障水资源安全。

关键词：清水河流域白河流域径流归因分析 Budyko模型

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Ti:Sapphire-Laser Pumped 20 at.% Yb:YAG Thin Chip with Continuous-Wave Laser Output of 356 mW at 1.053 μm

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Chinese Physics Letters 2000年第2期17卷 104-105页

作者： YANG pei-Zhi DENG pei-Zhen ZHANG Ying-Hua LIU Yu-Pu HUANG Gu-Song CHEN Wei XU Jun Shanghai Institute of Optics and Fine Mechanics Chinese Academy of SciencsesShanghai 201800 Shanghai Institute of Ceramics Chinese Academy of SciencesShanghai 200050

We analyzed the spectroscopic performances of Yb:YAG and developed an efficient room-temperature 20at.% Yb:YAG thin chip (6×6×0.5 mm) laser operating at 1.053μm pumped by Ti-sapphire laser operating at 940nm. Output power of 356 mW was obtained for an absorbed pump power of 784 mW. The slope efficiency was 69%, and the extrapolated threshold was 273mW. The slope efficiency was as high as 72% with absorbed pump power exceeding 730 mW.

关键词： Yb:YAG pump pumped

Image analysis of aggregate,mastic and air void phases for asphalt mixture

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交通运输工程学报 2013年第2期13卷 1-9页

作者： ADHIKARI Sanjeev YOU Zhan-ping HAO pei-wen WANG Hai-nian Department of Applied Engineering and Technology Morehead State University Key Laboratory for Special Area Highway Engineering of Ministry of Education Chang'an University Department of Civil and EnvironmentalEngineering Michigan Technological University

The shape characterization and spatial distribution of aggregate,mastic and air void phases for asphalt mixture were *** air void percentage asphalt mixtures,4%,7% and 8%,respectively,were cut into cross sections and polished.X-ray scanning microscope was used to capture aggregate,mastic,air void phase by the *** average of polygon diameter was chosen as a threshold to determine which aggregates would be retained on a given *** aggregate morphological image from scanned image was utilized by digital image processing method to calculate the gradation of aggregate and simulate the real *** result shows that the air void of asphalt mixture has influence on the correlation between calculation gradation and actual *** comparing 4.75 mm sieve size of 4%,7% and 8% air void asphalt mixtures,7% air void asphalt mixture has 55% higher than actual size gradation,8% air void asphalt mixture has 8% higher than actual size gradation,and 4% air void asphalt mixture has 3.71% lower than actual size gradation.4% air void asphalt mixture has the best correlation between calculation gradation and actual gradation comparing to other *** air void percentage of asphalt mixture has no obvious influence on the air void orientation,and three asphalt mixtures show the similar air orientation along the same direction.

关键词： road engineering asphalt mixture digital image processing air void distribution gradation

Performance measurement of broadband, wide-angle polarizing beam splitter

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第2期8卷 176-179页

作者： CHEN Wei-bin ZHENG Zhen-rong GU pei-fu ZHANG Yue-guang State Key Laboratory of Modern Optical Instrumentation Zhejiang University Hangzhou 310027 China

Polarizing beam splitter (PBS) is a critical optical component in projection display system because PBS performance greatly influences the contrast and brightness of the system. PBS performance is usually measured by spectrophotometer after coating and cementing, but the measured result cannot represent the actual performance in practice because people usually change the incident angle in one plane (horizontal plane) and do not consider the other plane (vertical plane). Geometrical polarization rotation occurring at reduced F-number influences the measuring precision of s-polarization transmittance (Ts) and p-polarization reflectance (Rp). A more accurate and practical way to measure the performance of broadband, wide-angle PBS is presented in this paper.

关键词： Polarizing beam splitter (PBS) Projection display Measurement Contrast

Dairy Consumption and Associations with Nutritional Status of Chinese Children and Adolescents

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Biomedical and Environmental Sciences 2019年第6期32卷 393-405页

作者： XU pei pei YANG Ti Ti XU Juan LI Li CAO Wei GAN Qian HU Xiao Qi PAN Hui ZHAO Wen Hua ZHANG Qian National Institute for Nutrition and Health Chinese Center for Disease Control and Prevention

Objective This study aimed to describe frequency and quantity of total dairy consumption of Chinese children and adolescents and explore the associations between dairy consumption and nutrition status, including stunting, wasting, overweight, and obesity. Methods Participants included 28,250 children and adolescents aged 6-17 years old. A food frequency questionnaire(FFQ) including 100 kinds of food was used to collect information about frequency and quantity of dairy consumption. Determination of stunting was with a height cutoff value for age and gender, and determination for wasting, overweight, and obesity was with BMI for age and gender. Results Of the total sample, 36.1% of children aged 6-17 reported consuming dairy food more than once per day(≥ 1/day). The average total dairy intake of all the participants was 126.7 g/day. For boys, dairy consumption had an inverse correlation with stunting and wasting after controlling for confounders. For girls, dairy consumption was negatively associated with stunting and obesity after controlling for confounders as above. Conclusion Dairy consumption in Chinese children and adolescents was relatively lower than that in developed countries, and was negatively associated with stunting and wasting for boys and with stunting and obesity for girls.

关键词： Dairy consumption Children and adolescents Nutrition status Association China

饲料中添加N-氨甲酰谷氨酸或牛磺酸对杂交鳢生长性能、肠道黏膜形态及肠道菌群的影响

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水生生物学报 2024年第4期48卷 579-591页

作者：李培佳闫辰侯冬强李敏彭凯黄文曹俊明赵红霞广东省农业科学院动物科学研究所广东省农业科学院水产研究中心广东省畜禽育种与营养研究重点实验室广州510640 华中农业大学水产学院武汉430070 广州飞禧特生物科技有限公司广州510640

实验旨在探讨饲料添加N-氨甲酰谷氨酸(NCG)或牛磺酸(Taurine)对杂交鳢(Channa maculata♀×***♂)幼鱼肠道生长、消化、抗氧化和肠道菌群的影响。实验选取初始体均重为(22.02±0.02)g的杂交鳢450尾,随机分为3个组,每组3个重复,每个重复5... 详细信息

实验旨在探讨饲料添加N-氨甲酰谷氨酸(NCG)或牛磺酸(Taurine)对杂交鳢(Channa maculata♀×***♂)幼鱼肠道生长、消化、抗氧化和肠道菌群的影响。实验选取初始体均重为(22.02±0.02)g的杂交鳢450尾,随机分为3个组,每组3个重复,每个重复50尾,分别投喂基础饲料以及在基础饲料中添加0.03%N-氨甲酰谷氨酸、1%牛磺酸的3种实验饲料,记作对照组,0.03%NCG组和1%Taurine组,饲喂8周。结果表明,饲料中添加0.03%NCG或1%Taurine可显著提高杂交鳢蛋白质沉积率(P<0.05),提高肠道淀粉酶和肌酸激酶活性(P<0.05),促进前肠肌层厚度、中肠绒毛宽度、中肠肌层厚度和后肠肌层厚度生长(P<0.05),增强肠道厚壁菌群和支原体属丰度(P<0.05),显著降低饲料系数和肠道丙二醛含量(P<0.05),显著降低肠道梭杆菌群和梭菌属丰度(P<0.05)。此外,饲料中添加0.03%NCG可显著提高杂交鳢肠道总抗氧化能力、过氧化物酶和谷胱甘肽过氧化物酶活性(P<0.05),显著缓解肠道病理状态(P<0.05),显著提高杂交鳢肠道胰蛋白酶、脂肪酶、γ-谷氨酰转移酶和钠钾ATP酶活性(P<0.05),促进前肠绒毛长度、前肠绒毛宽度和后肠肌层厚度生长(P<0.05),并显著提高肠道OUT占比、Chao和Ace指数(P<0.05),增强肠道菌群丰富度和多样性(P<0.05)。结果表明饲料中添加NCG在增强肠道抗氧化活性,缓解肠道氧化损伤方面优于添加牛磺酸,但饲料添加牛磺酸可以增强肠道消化酶活性,增强肠道菌群丰富度和多样性,维持肠道稳态并促进肠道生长,其作用效果优于补充NCG。

关键词： N-氨甲酰谷氨酸牛磺酸生长性能肠道杂交鳢

Phase Structure, Microstructure and Electrical Properties of K_xNa_((1-x))NbO_3 Piezoelectric Ceramics with Different K/Na Ratio

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Journal of Wuhan University of Technology(Materials Science) 2019年第1期34卷 30-34页

作者： CHEN Jianchao ZHAO pei Key Laboratory for Green Chemical Process of Ministry of Education Hubei Key Laboratory of Plasma Chemistry and Advanced Materials School of Material Science and Engineering Wuhan Institute of Technology Faculty of Materials and Chemistry China University of Geosciences State Key Laboratory of Geological Process and Mineral Resources China University of Geosciences

The K_xNa_((1-x))NbO_3(x=0.45, 0.46, 0.47, 0.48, 0.49, 0.50) lead-free piezoelectric ceramics was fabricated by conventional solid-state sintering method. It was found that the ratio of alkaline metal would affect the microstructure, bulk density, and optimum sintering temperatures of ceramics. Meanwhile, the electrical properties were also influenced by modulating the K/Na ratio, exhibiting corresponding composition-dependent properties. The optimum electrical properties of K_xNa_((1-x))NbO_3 such as piezoelectric constant d_(33) = 115 pC/N, mechanical quality factor Q_m = 20, Curie temperature Tc = 365 ~oC, ε_(33)~T/ε_0= 588.1, dielectric loss tan δ = 0.024, bulk density(ρ) = 3.08 g/cm^3, remnant polarization(P_r) = 8.87 μC/cm^2 and coercive field(Ec) = 13.79 kV/cm were obtained at x = 0.46.

关键词： lead-free piezoelectric ceramics solid-state sintering K/Na ratio electrical properties

Effectiveness of hand self-shiatsu to improve sleep following sport-related concussion in young athletes: a proof-of-concept study

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Journal of Integrative Medicine 2019年第1期17卷 24-29页

作者： pei Qin Bruce D.Dick Ada Leung Cary A.Brown Faculty of Rehabilitation Medicine University of Alberta Department of Anesthesiology and Pain Medicine Faculty of Medicine and Dentistry University of Alberta Department of Occupational Therapy Faculty of Rehabilitation Medicine University of Alberta

Objective: The prevalence of sport-related concussion(SRC) is high and results in a number of serious health consequences. One area that has received minimal research is the relationship between SRC and sleep. The literature shows that sleep deficiency is a frequent negative consequence of SRC. At the same time, sleep deficiency delays recovery from SRC and contributes added risk of symptom recurrence.A 2014 study of chronic pain patients who learned to apply the complementary and alternative medicine intervention hand self-shiatsu(HSS) had promising, sleep-promoting results that warrant further investigation with other populations. This proof-of-concept study explored the feasibility of HSS as an intervention to promote sleep onset and continuity for young adults with ***: This study employed a prospective case-series design, where participants act as their own controls. Baseline and follow-up data included standardized self-reported assessment tools and sleep ***: Seven athletes, aged between 18 and 25 years, participated in the study. Although statistically significant improvement in actigraphy sleep scores between baseline and follow-up was not achieved,metrics for sleep quality and daytime fatigue showed significant ***: These findings support the hypothesis that HSS has the potential to improve sleep and reduce daytime fatigue in young postconcussion athletes. This pilot study provides guidance to refine research protocols and lays a foundation for further, large-sample, controlled studies.

关键词： Concussion Insomnia Youth Complementary and alternative medicine Self-management