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Longitudinal assessment of peripheral organ metabolism and the gut microbiota in an APP/PS1 transgenic mouse model of Alzheimer’s disease
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作者 Hongli Li Jianhua Huang +4 位作者 Di Zhao Lemei Zhu Zheyu Zhang Min Yi Weijun Peng 《Neural Regeneration Research》 SCIE CAS 2025年第10期2982-2997,共16页
Alzheimer’s disease not only affects the brain,but also induces metabolic dysfunction in peripheral organs and alters the gut microbiota.The aim of this study was to investigate systemic changes that occur in Alzhei... Alzheimer’s disease not only affects the brain,but also induces metabolic dysfunction in peripheral organs and alters the gut microbiota.The aim of this study was to investigate systemic changes that occur in Alzheimer’s disease,in particular the association between changes in peripheral organ metabolism,changes in gut microbial composition,and Alzheimer’s disease development.To do this,we analyzed peripheral organ metabolism and the gut microbiota in amyloid precursor protein-presenilin 1(APP/PS1)transgenic and control mice at 3,6,9,and 12 months of age.Twelve-month-old APP/PS1 mice exhibited cognitive impairment,Alzheimer’s disease-related brain changes,distinctive metabolic disturbances in peripheral organs and fecal samples(as detected by untargeted metabolomics sequencing),and substantial changes in gut microbial composition compared with younger APP/PS1 mice.Notably,a strong correlation emerged between the gut microbiota and kidney metabolism in APP/PS1 mice.These findings suggest that alterations in peripheral organ metabolism and the gut microbiota are closely related to Alzheimer’s disease development,indicating potential new directions for therapeutic strategies. 展开更多
关键词 Alzheimer’s disease APP/Ps1 mice brain-kidney axis gut microbiota heart-brain axis liver-brain axis lung-brain axis microbiota-gut-brain axis peripheral organ metabolism spleen-brain axis
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The research progress on food organism culture and technology utilization in crab seed production in ponds in China 被引量:3
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作者 Jibing Qi Xiaolian Gu +2 位作者 Lingbo Ma Zhenguo Qiao Kai Chen 《Agricultural Sciences》 2013年第10期563-569,共7页
Eriocheirsinensis, Portunus trituberculatus and Scylla paramamosain are important commercial culture crab species in China. Traditional factory breeding of crabs depends on Artemia nauplius. The rising price of Artemi... Eriocheirsinensis, Portunus trituberculatus and Scylla paramamosain are important commercial culture crab species in China. Traditional factory breeding of crabs depends on Artemia nauplius. The rising price of Artemia cysts has led to the decline of the economic benefit of the crab breeding factory. Factory crab breeding has been gradually replaced by pond breeding in recent years. E. sinensis and P. trituberculatus have been bred mainly in ponds. Meanwhile, S. paramamosain is still mainly bred in factories because of the crudeness of pond breeding. The research progress on food organism utilization in the three species of commercially bred crabs was reviewed in this paper. In the workshop seeds production, rotifer and Artemia nauplii were necessary in the early stages from zoea I to zoea II in the three crab species. Adult artemia, minced fish and shellfish were fed to the larvae in the later zoea stages from zoea III to Megalopa.?The rising of the price of artemia eggs made people find other feed organism to replace artemia. Copepods have been used in crab seeds production in pond from zoea III stage to replace artemia in recent years, which has reduced the cost of seeds production. 展开更多
关键词 FOOD organisms CRAB sEEDs ponds
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WO_(3)/Zn_(0.5)Cd_(0.5)S S型异质结光催化产氢耦合有机物转化机理研究 被引量:1
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作者 曹爽 钟博 +2 位作者 别传彪 程蓓 徐飞燕 《物理化学学报》 SCIE CAS CSCD 北大核心 2024年第5期50-54,共5页
开发新型纳米材料实现光催化产氢耦合有机物转化、提高太阳能到化学能的转换效率,在解决能源和环境危机方面具有巨大潜力。三元金属硫化物具有可调控的带隙和优异的可见光响应,在光催化分解水产氢方面引起了广泛关注。其中,Zn_(0.5)Cd_(... 开发新型纳米材料实现光催化产氢耦合有机物转化、提高太阳能到化学能的转换效率,在解决能源和环境危机方面具有巨大潜力。三元金属硫化物具有可调控的带隙和优异的可见光响应,在光催化分解水产氢方面引起了广泛关注。其中,Zn_(0.5)Cd_(0.5)S是一种带隙较窄、导带位置较高、耐光腐蚀的还原型光催化剂;然而,单一Zn_(0.5)Cd_(0.5)S中光生电子和空穴的复合率较高,只有少部分光生载流子参与光催化反应,导致量子效率较低而无法达到实际需求。WO_(3)是一种典型的氧化型光催化剂,具有较低的价带位置和较强的氧化能力,是与Zn_(0.5)Cd_(0.5)S耦合构建S型异质结的理想半导体。基于此,本文通过静电纺丝和水热方法将Zn_(0.5)Cd_(0.5)S纳米片垂直生长在WO_(3)纳米纤维上,制备了具有核壳结构的WO_(3)/Zn_(0.5)Cd_(0.5)S异质结。功函数的差异驱动Zn_(0.5)Cd_(0.5)S的电子转移到WO_(3)上,在界面处形成内建电场并使能带弯曲。通过原位光照X射线光电子能谱、电子顺磁共振和时间分辨荧光光谱分析,发现在内建电场、弯曲能带和库仑吸引力的作用下,WO_(3)导带上的光生电子迁移到Zn_(0.5)Cd_(0.5)S价带上并与其光生空穴复合,表明WO_(3)和Zn_(0.5)Cd_(0.5)S之间形成了S型异质结,实现了具有强氧化还原能力的载流子的高效分离。得益于独特的S型光催化机制以及反应物在催化剂表面的有效吸附与活化,没有贵金属助催化剂的情况下,WO_(3)/Zn_(0.5)Cd_(0.5)S异质结在产氢(715 μmol·g^(-1)·h^(-1))和乳酸转化为丙酮酸方面表现出增强的光催化活性,实现了光生电子和空穴的高效利用。原位漫反射傅里叶变换红外光谱和密度泛函理论计算揭示了光催化产氢和有机物转化的反应机理。本工作为设计和研究新型S型异质结光催化剂、实现高效产氢耦合有机物转化提供了新的见解。 展开更多
关键词 三氧化钨 s型异质结 产氢 有机物转化 化学吸附与活化
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Persulfate activation by single-atom catalysts for the removal of organic pollutants: A review
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作者 Yuqi Liu Huanxin Zhao 《Resources Chemicals and Materials》 2023年第1期63-79,共17页
Single-atom catalysts(SACs)have received enormous attention in the field of catalysis due to their inherent mer-its,such as nearly 100%atomic efficiency,environmental friendliness,and unique physicochemical properties... Single-atom catalysts(SACs)have received enormous attention in the field of catalysis due to their inherent mer-its,such as nearly 100%atomic efficiency,environmental friendliness,and unique physicochemical properties.The emerging SACs have facilitated the development and advancement of catalysis.The rapidly increasing ap-plications of SACs in various fields,including oxygen evolution reaction,organic synthesis,hydrogen evolution reaction,and CO_(2) reduction,reflect their enormous potential.Recently,SACs have been extensively used in per-sulfate(PS)activation for refractory organic pollutants degradation in the aqueous environment.SACs exhibit distinct advantages of both homogeneous and heterogeneous catalysis,demonstrating a prospective application in PS activation.This review first introduces the synthesis and characterization schemes of SACs in PS activa-tion.Second,the factors influencing PS activation by SACs,including coordination numbers,type of coordination atoms,the spin state of metal sites,type of carriers,and the loading amount of metal atoms,are described.Third,the applications and activation mechanisms of SACs are summarized.Finally,the opportunities and challenges confronted by SACs and their future development prospects in advanced oxidation processes(AOPs)are put forward. 展开更多
关键词 Persulfate activation single-atom catalyst s AOPs organic pollutants
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In-situ preparation of Cu-BTC modified with organic amines for H_(2)S removal under ambient conditions
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作者 Zhelin Su Mingxian Duan +5 位作者 Yeshuang Wang Huiling Fan Zhen Tian Zhaohui Chen Chao Yang Ju Shangguan 《Resources Chemicals and Materials》 2023年第2期143-150,共8页
Amine modification is an effective strategy to improve the H_(2)S removal performance of Cu-BTC.In order to avoid the problem of pore blockage after amine modification in post synthesis impregnation,herein a series of... Amine modification is an effective strategy to improve the H_(2)S removal performance of Cu-BTC.In order to avoid the problem of pore blockage after amine modification in post synthesis impregnation,herein a series of Cu-BTC modified with organic amine adsorbents were prepared via an in-situ one-pot method and the H_(2)S removal performance under ambient conditions was tested.It is found that the introduced organic amines,depending on the types of amine selected,have a significant influence on the growth of Cu-BTC and its textural properties.The H_(2)S removal performance on the as-prepared materials suggested that the amine modified samples remarkably improved the H_(2)S removal capacities with an order of BA-Cu-BTC>TEA-Cu-BTC>TEOA-Cu-BTC>Cu-BTC.Besides the enlarged surface area and the increased mesopores volumes,BA has the advantages of smaller steric hindrance and-NH_(2)groups,among which the former increased the accessibility of Cu active sites while the latter acted as additional active sites for H_(2)S capturing,thus affording BA-Cu-BTC highest breakthrough capacity of 77.3 mg S/g.Overall,this study elaborates the effect of organic amines in-situ modification on the Cu-BTC structure and desulfurization. 展开更多
关键词 In-situ preparation organic amines Cu-BTC H_(2)s adsorption
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可见光氧化还原协同镍催化构建C—S键偶联反应
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作者 李申 剧芳 +2 位作者 张舒雅 丁晶晶 康舒铭 《合成化学》 CAS 2024年第5期414-423,共10页
在可见光和过渡金属镍协同催化体系中,可见光催化可以通过单电子氧化或还原过程推动过渡金属镍催化,又可以通过能量转移过程推动镍催化循环。这为传统过渡金属催化的偶联反应提供了更多可能性。同时,大多数光催化剂使用基于Ru和Ir金属... 在可见光和过渡金属镍协同催化体系中,可见光催化可以通过单电子氧化或还原过程推动过渡金属镍催化,又可以通过能量转移过程推动镍催化循环。这为传统过渡金属催化的偶联反应提供了更多可能性。同时,大多数光催化剂使用基于Ru和Ir金属的配合物,不仅价格昂贵,还会在工业生产中存在金属残留。本文开发了一种高效且经济的协同催化体剂(Nap)_(2)PXZ-bpy-Ni,以吩噁嗪为有机光催化剂,NiBr_(2)·DME为镍催化剂,联吡啶作为配体,通过Click的方式将光催化剂和联吡啶镍催化剂连接起来。实验结果表明:在1%(物质的量分数,下同)催化剂负载下反应12H,C—S键偶联产物收率可达73%~95%,实现了高效的催化效率并显示出较好的官能团适用性和底物普适性。最后通过自由基捕捉实验推测了该反应可能的机理。 展开更多
关键词 光催化 镍催化 协同催化 有机光敏剂 C—s偶联反应
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大型石化企业储罐VOC_(S)治理改造与节能应用探究 被引量:1
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作者 王楠 《石油化工安全环保技术》 CAS 2023年第3期59-63,68,I0004,共7页
为减小因丁辛醇罐区储罐排放尾气引起的环境污染和其它安全隐患,通过对不同治理技术进行研究,择优应用冷却回收技术对含100%丁醛组分的醛储罐排放尾气进行回收。采用新型储罐密封技术对80%以上为丁醛的轻组分储罐、含60%左右丁醇的重组... 为减小因丁辛醇罐区储罐排放尾气引起的环境污染和其它安全隐患,通过对不同治理技术进行研究,择优应用冷却回收技术对含100%丁醛组分的醛储罐排放尾气进行回收。采用新型储罐密封技术对80%以上为丁醛的轻组分储罐、含60%左右丁醇的重组分储罐及含20%左右丁醇的杂醇储罐进行处理,以满足降低挥发性有机物量的目标,实现罐区尾气异味治理,有效减少现场异味,保护环境。 展开更多
关键词 冷却回收 储罐密封 挥发性有机物 异味治理
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Spectral Characterization of Colored Dissolved Organic Matter for Productive Inland Waters and Its Source Analysis 被引量:5
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作者 SONG Kaishan LI Lin +3 位作者 Lenore TEDESCO Nicolas CLERCIN LI Linhai SHI Kun 《Chinese Geographical Science》 SCIE CSCD 2015年第3期295-308,共14页
This study examined the spatiotemporal dynamics of colored dissolved organic matter (CDOM) and spectral slope (S), and further to analyze its sources in three productive water supplies (Eagle Creek, Geist and Mor... This study examined the spatiotemporal dynamics of colored dissolved organic matter (CDOM) and spectral slope (S), and further to analyze its sources in three productive water supplies (Eagle Creek, Geist and Morse reservoirs) from Indiana, USA. The re- sults showed that he absorption coefficient aCDOM(440) ranged from 0.37 m-1 to 3.93 m-1 with an average of 1.89 ± 0.76 m-1 (±SD) for the aggregated dataset, and S varied from 0.0048 nm -1 to 0.0239 nm-1 with an average of 0.0108 ±0.0040 nmI. A significant relation- ship between S and aCDOM(440) can be fitted with a power equation (S = 0.013 × aCDOM(440)-0.42, R2 = 0.612), excluding data from Geist Reservoir during high flow (12 April 2010) and the Morse Reservoir on 25 June 2010 due to a T-storm achieves even higher determina- tion coefficient (R2 = 0.842). Correlation analysis indicated that aCDOM(440) has strong association with inorganic suspended matter (ISM) concentration (0.231 〈 R2 〈 0.786) for each of the field surveys, and this trend followed the aggregated datasets (R2 = 0.447, p 〈 0.001). In contrast, chlorophyll-a was only correlated with aCDOM(440) in summer and autumn (0.081 〈 R2 〈 0.763), indicating that CDOM is mainly from terrigenous sources in early spring and that phytoplankton contributed during the algal blooming season. The S value was used to characterize CDOM origin. The results indicate that the CDOM source is mainly controlled by hydrological varia- tions, while phytoplankton originated organic matter also closely linked with CDOM dynamics in three productive reservoirs. 展开更多
关键词 absorption coefficient colored dissolved organic matter (CDOM) CHLOROPHYLL-A spectral slope s inorganic suspendedmatter (IsM)
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Sequential organ failure assessment score is superior to other prognostic indices in acute pancreatitis 被引量:15
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作者 Thomas Zheng Jie Teng Jun Kiat Thaddaeus Tan +5 位作者 Samantha Baey Sivaraj K Gunasekaran Sameer P Junnarkar Jee Keem Low Cheong Wei Terence Huey Vishal G Shelat 《World Journal of Critical Care Medicine》 2021年第6期355-368,共14页
BACKGROUND Acute pancreatitis(AP)is a common surgical condition,with severe AP(SAP)potentially lethal.Many prognostic indices,including;acute physiology and chronic health evaluation II score(APACHE II),bedside index ... BACKGROUND Acute pancreatitis(AP)is a common surgical condition,with severe AP(SAP)potentially lethal.Many prognostic indices,including;acute physiology and chronic health evaluation II score(APACHE II),bedside index of severity in acute pancreatitis(BISAP),Glasgow score,harmless acute pancreatitis score(HAPS),Ranson’s score,and sequential organ failure assessment(SOFA)evaluate AP severity and predict mortality.AIM To evaluate these indices'utility in predicting severity,intensive care unit(ICU)admission,and mortality.METHODS A retrospective analysis of 653 patients with AP from July 2009 to September 2016 was performed.The demographic,clinical profile,and patient outcomes were collected.SAP was defined as per the revised Atlanta classification.Values for APACHE II score,BISAP,HAPS,and SOFA within 24 h of admission were retrospectively obtained based on laboratory results and patient evaluation recorded on a secure hospital-based online electronic platform.Data with<10%missing data was imputed via mean substitution.Other patient information such as demographics,disease etiology,and patient outcomes were also derived from electronic medical records.RESULTS The mean age was 58.7±17.5 years,with 58.7%males.Gallstones(n=404,61.9%),alcohol(n=38,5.8%),and hypertriglyceridemia(n=19,2.9%)were more common aetiologies.81(12.4%)patients developed SAP,20(3.1%)required ICU admission,and 12(1.8%)deaths were attributed to SAP.Ranson’s score and APACHE-II demonstrated the highest sensitivity in predicting SAP(92.6%,80.2%respectively),ICU admission(100%),and mortality(100%).While SOFA and BISAP demonstrated lowest sensitivity in predicting SAP(13.6%,24.7%respectively),ICU admission(40.0%,25.0%respectively)and mortality(50.0%,25.5%respectively).However,SOFA demonstrated the highest specificity in predicting SAP(99.7%),ICU admission(99.2%),and mortality(98.9%).SOFA demonstrated the highest positive predictive value,positive likelihood ratio,diagnostic odds ratio,and overall accuracy in predicting SAP,ICU admission,and mortality.SOFA and Ranson’s score demonstrated the highest area under receiver-operator curves at 48 h in predicting SAP(0.966,0.857 respectively),ICU admission(0.943,0.946 respectively),and mortality(0.968,0.917 respectively).CONCLUSION The SOFA and 48-h Ranson’s scores accurately predict severity,ICU admission,and mortality in AP,with more favorable statistics for the SOFA score. 展开更多
关键词 PANCREATITIs severity scoring Intensive care unit Mortality sequential organ Failure Assessment score Ranson’s score
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Centennial-scale records of total organic carbon in sediment cores from the South Yellow Sea, China 被引量:1
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作者 祝青 林佳 +4 位作者 洪跃辉 袁丽蓉 刘金钟 徐小明 王江海 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2018年第1期128-138,共11页
Global carbon cycling is a significant factor that controls climate change.The centennial-scale variations in total organic carbon(TOC)contents and its sources in marginal sea sediments may reflect the influence of hu... Global carbon cycling is a significant factor that controls climate change.The centennial-scale variations in total organic carbon(TOC)contents and its sources in marginal sea sediments may reflect the influence of human activities on global climate change.In this study,two fine-grained sediment cores from the Yellow Sea Cold Water Mass of the South Yellow Sea were used to systematically determine TOC contents and stable carbon isotope ratios.These results were combined with previous data of black carbon and (210)~Pb dating from which we reconstructed the centennial-scale initial sequences of TOC,terrigenous TOC(TOC_(ter))and marine autogenous TOC(TOC_(mar))after selecting suitable models to correct the measured TOC(TOC_(cor)).These sequences showed that the TOC_(ter) decreased with time in the both cores while the TOC_(mar) increased,particularly the rapid growth in core H43 since the late 1960s.According to the correlation between the Huanghe(Yellow)River discharge and the TOC_(cor),TOC_(ter),or TOC_(mar),we found that the TOC_(ter) in the two cores mainly derived from the Huanghe River and was transported by it,and that higher Huanghe River discharge could strengthen the decomposition of TOC_(mar).The newly obtained initial TOC sequences provide important insights into the interaction between human activities and natural processes. 展开更多
关键词 organic carbon Middelburg’s model Yellow sea
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N/S codoping modification based on the metal organic frameworkderived carbon to improve the electrochemical performance of different energy storage devices 被引量:1
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作者 Ziyi Zhu Xue Li +4 位作者 Zhong Zhang Qi Meng Wenjia Zhang Peng Dong Yingjie Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第11期394-403,I0011,共11页
Carbon-based materials have become a research hotspot in the field of energy storage devices in recent years due to their abundant resources,low cost,and environmental friendliness.However,the low capacity and poor hi... Carbon-based materials have become a research hotspot in the field of energy storage devices in recent years due to their abundant resources,low cost,and environmental friendliness.However,the low capacity and poor high rate performance still constitute great challenges.Metal organic framework-derived carbon has been widely researched because of its high porosity,tunable structure,and good conductivity.In this work,N/S codoped hierarchical porous carbon microspheres were prepared by a high-temperature heat treatment and atomic doping process using a zinc-based organic framework as the precursor.When used as a potassium-ion battery anode,it has a high reversible specific capacity(435.7 mAh g^(-1)),good rate performance(133.5 mAh g^(-1)at 10,000 m A g^(-1)),and long-term cycling stability(73.2%capacity retention after the 2500th cycle).The potassium storage mechanism of the derived carbon was explained by various electrochemical analysis methods and microstructure characterization techniques,and the relationship between the structural characteristics and electrochemical properties was researched.In a supercapacitor,the porous carbon material exhibits a specific capacitance of 307.2 F g^(-1)at a current density of 0.2 A g^(-1)in a KOH aqueous solution and achieves a retention rate of 99.88%after 10,000 cycles.The assembled symmetric supercapacitor device delivers a high energy density of 6.69 Wh kg^(-1),with a corresponding power density of 2500 W kg^(-1).In addition,density functional theory calculations further confirmed that N/S codoping can improve the adsorption capacities of potassium and hydroxyl ions in the derived carbon. 展开更多
关键词 N/s codoped Carbon microspheres Metal organic frameworks Potassium-ion batteries sUPERCAPACITORs
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A Fractional Drift Diffusion Model for Organic Semiconductor Devices 被引量:1
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作者 Yi Yang Robert A.Nawrocki +1 位作者 Richard M.Voyles Haiyan H.Zhang 《Computers, Materials & Continua》 SCIE EI 2021年第10期237-266,共30页
Because charge carriers of many organic semiconductors(OSCs)exhibit fractional drift diffusion(Fr-DD)transport properties,the need to develop a Fr-DD model solver becomes more apparent.However,the current research on ... Because charge carriers of many organic semiconductors(OSCs)exhibit fractional drift diffusion(Fr-DD)transport properties,the need to develop a Fr-DD model solver becomes more apparent.However,the current research on solving the governing equations of the Fr-DD model is practically nonexistent.In this paper,an iterative solver with high precision is developed to solve both the transient and steady-state Fr-DD model for organic semiconductor devices.The Fr-DD model is composed of two fractionalorder carriers(i.e.,electrons and holes)continuity equations coupled with Poisson’s equation.By treating the current density as constants within each pair of consecutive grid nodes,a linear Caputo’s fractional-order ordinary differential equation(FrODE)can be produced,and its analytic solution gives an approximation to the carrier concentration.The convergence of the solver is guaranteed by implementing a successive over-relaxation(SOR)mechanism on each loop of Gummel’s iteration.Based on our derivations,it can be shown that the Scharfetter–Gummel discretization method is essentially a special case of our scheme.In addition,the consistency and convergence of the two core algorithms are proved,with three numerical examples designed to demonstrate the accuracy and computational performance of this solver.Finally,we validate the Fr-DD model for a steady-state organic field effect transistor(OFET)by fitting the simulated transconductance and output curves to the experimental data. 展开更多
关键词 Fractional drift diffusion model Gummel’s iteration Caputo’s fractional-order ordinary differential equation organic field effect transistor
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Effects of Organic Fertilizers Made from Distiller's Grains on the Growth and Development of Flue-cured Tobacco 被引量:2
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作者 Sheng JIANG Miao YANG +8 位作者 Fei XIONG Yonghui ZHANG Chun XIA Jiao GUAN Kefan CAI Juntao HE Yuangai ZHANG Fei WANG Fuzhao NIAN 《Agricultural Biotechnology》 CAS 2018年第3期158-160,164,共4页
Pot experiments were conducted to study the effects of different organic fertilizers made from distiller's grains on the physiological characteristics and growth of flue-cured tobacco. The results showed that the agr... Pot experiments were conducted to study the effects of different organic fertilizers made from distiller's grains on the physiological characteristics and growth of flue-cured tobacco. The results showed that the agronomic traits and biomass of flue-cured tobacco in the three treatments were higher than that of the control group,and the mixed application of different organic fertilizers made from distiller's grains and compound fertilizer could promote the growth and development of flue-cured tobacco significantly. 展开更多
关键词 organic fertilizers made from distiller's grains Agronomic characters BIOMAss Chlorophyll content
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社会组织参与困境儿童社会支持网络构建的服务策略研究--以广州市S组织困境儿童服务项目为例 被引量:3
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作者 朱媛媛 王兴龙 吴君霞 《社会工作与管理》 2023年第2期18-29,共12页
要妥善回应深化改革过程中困境儿童多元化的需求,须从困境儿童社会支持着手,通过发挥社会组织联动多元主体的作用来筑实困境儿童社会支持网络。研究聚焦S组织困境儿童服务实践策略,分析其回应需求的服务过程,旨在为社会组织参与构建困... 要妥善回应深化改革过程中困境儿童多元化的需求,须从困境儿童社会支持着手,通过发挥社会组织联动多元主体的作用来筑实困境儿童社会支持网络。研究聚焦S组织困境儿童服务实践策略,分析其回应需求的服务过程,旨在为社会组织参与构建困境儿童支持网络提供实务参考。研究发现,S组织在开展困境儿童服务时能够充分发挥枢纽平台优势,在一定程度上促进了儿童主体发展和多元主体参与,但组织存在建设局限性、服务内容与形式创新不足、服务不够规范、机制缺失等方面的问题。推动儿童福利事业发展的关键在于要坚持政府主导的公共服务供给格局,拓宽社会参与渠道和门槛,整合跨界创新力量,动员多元主体在困境儿童服务中积极投入服务和资源,强化其社会支持网络。 展开更多
关键词 社会组织 困境儿童 社会支持 网络
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Group Purchasing Organizations (GPOs) in the U.S.: Development and Reform 被引量:1
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作者 Jin Jing Xiong Jiamei +1 位作者 Yang Yue Huang Zhe 《Asian Journal of Social Pharmacy》 2019年第3期100-109,共10页
Objective To study the characteristics, specific functions and policy improvement process of the Group Purchasing Organizations (GPOs) in the U.S. and to provide references for drug group purchasing practices in China... Objective To study the characteristics, specific functions and policy improvement process of the Group Purchasing Organizations (GPOs) in the U.S. and to provide references for drug group purchasing practices in China. Methods Domestic and foreign relevant literatures, websites were reviewed or searched to analyze the functions and policy improvement process of the GPOs in the U.S. so as to provide references for drug group purchasing practices in China. Results and Conclusion As a third party in the U.S. GPOs has formed a relatively integrated business process and projects service system after long-term development. Supported by corresponding policies and industrial regulations, GPOs have made a great contribution to control the growth of medical and healthcare expenses and improve the efficiency of medical institutions, and its development experience can enlighten the practices in China. 展开更多
关键词 group PURCHAsING organIZATION (GPO) drug PURCHAsE the U.s.
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双酚S对秀丽隐杆线虫精子生成相关基因表达的影响
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作者 唐娇 谭剑斌 +4 位作者 茅莉娜 张紫虹 李文立 胡帅尔 赵敏 《癌变.畸变.突变》 CAS 2023年第3期183-186,共4页
目的:探讨双酚S对模式生物秀丽隐杆线虫精子生成相关基因表达的影响。方法:根据双酚S的急性毒性试验结果确定本研究剂量为0、3、30、300μmol/L,对同步化至L4期的线虫进行24 h暴露,测定其子代数目并用实时荧光定量PCR(qPCR)检测akt-1、s... 目的:探讨双酚S对模式生物秀丽隐杆线虫精子生成相关基因表达的影响。方法:根据双酚S的急性毒性试验结果确定本研究剂量为0、3、30、300μmol/L,对同步化至L4期的线虫进行24 h暴露,测定其子代数目并用实时荧光定量PCR(qPCR)检测akt-1、swm-1、try-5、spe-4、spe-6基因表达水平。结果:秀丽隐杆线虫于双酚S中暴露24 h后,其半数致死浓度(LC50)为2773.672μmol/L;与对照组相比,暴露后的L4期秀丽隐杆线虫在双酚S剂量为3、30、300μmol/L时子代数目均显著降低(P<0.05或P<0.01);akt-1 mRNA在3μmol/L时的表达水平升高(P<0.05);swm-1、try-5、spe-4、spe-6 mRNA在30和300μmol/L时表达水平均升高(P<0.05或P<0.01)。结论:双酚S对秀丽隐杆线虫精子生成相关基因表达有影响。 展开更多
关键词 秀丽隐杆线虫 双酚s 精子生成 模式生物
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Short-term influence of anaerobically-digested and conventional swine manure, and N fertilizer on organic C and N, and available nutrients in two contrasting soils
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作者 Sukhdev S. Malhi R. L. Lemke +1 位作者 M. Stumborg F. Selles 《Agricultural Sciences》 2012年第5期678-696,共19页
A three-year (2006-2008) field experiment was conducted at Swift Current and Star City in Saskatchewan to determine the short-term in-fluence of land-applied anaerobically digested swine manure (ADSM), conventionally ... A three-year (2006-2008) field experiment was conducted at Swift Current and Star City in Saskatchewan to determine the short-term in-fluence of land-applied anaerobically digested swine manure (ADSM), conventionally treated swine manure (CTSM) and N fertilizer on total organic C (TOC), total organic N (TON), light fraction organic C (LFOC), light fraction organic N (LFON) and pH in the 0 - 7.5 and 7.5 - 15 cm soil layers, and ammonium-N, nitrate-N, extractable P, exchangeable K and sulphate-S in the 0 - 15, 15 - 30, 30 - 60, 60 - 90 and 90 - 120 cm soil layers. Treatments included spring and autumn applications of CTSM and ADSM at a 1x rate (10,000 and 7150 L·ha-1, respectively) applied each year, a 3x rate (30,000 and 21,450 L·ha-1, respectively) applied once at the beginning of the experiment, plus a treatment receiving commercial fertilizer (UAN at 60 kg·N·ha-1·yr-1) and a zero-N control. There was no effect of swine manure rate, type and application time on soil pH. Mass of TOC and TON in the 15 cm soil layer increased significantly with swine manure application compared to the control, mainly at the Swift Current site, with greater increases from 3x rate than 1x rate (by 2.21 Mg·C·ha-1 and 0.167 Mg·N·ha-1). Compared to the control, mass of LFOC and LFON in the 15 cm soil layer increased with swine manure application at sites, with greater increases from 3x rate than 1x rate (by 287 kg·C·ha-1 and 26 kg·N·ha-1 at Star City, and by 194 kg·C·ha-1 and 19·kg·N ha-1 at Swift Current). Mass of TOC and TON in soil layer was tended to be greater with ADSM than CTSM, but mass of LFOC and LFON in soil was greater with CTSM than ADSM. Mass of TOC, TON, LFOC and LFON in soil also increased with annual N fertilizer application compared to the control (by 3.2 Mg·C·ha-1 for TOC, 0.195 Mg·N·ha-1 for TON, 708 kg·C·ha-1 for LFOC and 45 kg·N·ha-1 for LFON). In conclusion, our findings suggest that the quantity and quality of organic C and N in soil can be affected by swine manure rate and type, and N fertilization even after three years, most likely by influencing inputs of C and N through crop residue, and improve soil quality. 展开更多
关键词 ANAEROBIC DIGEsTION Available N P K and s organic C and N soil sWINE MANURE
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The Function,Future and Support Elements of Farmer Cooperative Economy Organization
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作者 Jing GAO Peng XIE 《Asian Agricultural Research》 2014年第5期105-108,共4页
The nature of farmer cooperative economy organization( known as FCEO) determines the fact that the economic effects of farmer cooperative economy organization are as important as its social effects. Many experts,howev... The nature of farmer cooperative economy organization( known as FCEO) determines the fact that the economic effects of farmer cooperative economy organization are as important as its social effects. Many experts,however,now would only focus on its economic function, and either neglect or weaken its social influence. Therefore,this paper introduces the theoretical foundation of the farmer cooperative economy organization,and studies the nature of cooperative economics. Based on those typical cases,the future of cooperative organization and four supporting elements were put forward in this paper. 展开更多
关键词 FARMER COOPERATIVE ECONOMY organIZATION Function s
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Direct and Indirect Excitons in Two-Dimensional Covalent Organic Frameworks
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作者 Shan Sun Hui-zhong Ma +1 位作者 Xiao Zhang Yu-chen Ma 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2020年第5期569-577,I0008-I0010,I0078,共13页
Highly luminescent bulk two-dimensional covalent organic frameworks(COFs)attract much attention recently.Origin of their luminescence and their large Stokes shift is an open question.After first-principles calculation... Highly luminescent bulk two-dimensional covalent organic frameworks(COFs)attract much attention recently.Origin of their luminescence and their large Stokes shift is an open question.After first-principles calculations on two kinds of COFs using the GW method and Bethe-Salpeter equation,we find that monolayer COF has a direct band gap,while bulk COF is an indirect band-gap material.The calculated optical gap and optical absorption spectrum for the direct excitons of bulk COF agree with the experiment.However,the calculated energy of the indirect exciton,in which the photoelectron and the hole locate at the conduction band minimum and the valence band maximum of bulk COF respectively,is too low compared to the fluorescence spectrum in experiment.This may exclude the possible assistance of phonons in the luminescence of bulk COF.Luminescence of bulk COF might result from exciton recombination at the defects sites.The indirect band-gap character of bulk COF originates from its AA-stacked conformation.If the conformation is changed to the AB-stacked one,the band gap of COF becomes direct which may enhance the luminescence. 展开更多
关键词 Covalent organic frameworks LUMINEsCENCE EXCITONs Many-body Green’s function theory
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Quality Safety Standards of Organic Mango
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作者 Kui LIN Riji WEI +3 位作者 Zheng ZHANG Zhaojun HUANG Yankun PAN Daoping HUANG 《Asian Agricultural Research》 2013年第4期126-128,138,共4页
This article conducts a brief analysis of the factors that affect the quality safety of organic mango, and discusses the organic production measures for improving the quality and quality safety of mango, including the... This article conducts a brief analysis of the factors that affect the quality safety of organic mango, and discusses the organic production measures for improving the quality and quality safety of mango, including the choice of environment of place of origin, varieties and seedlings, fertilizers and fertilization, plant protection products and other production inputs. A test is carried out in 0.667 hm2 of base in Tianyang County, Baise City. Content of lead, arsenic and 14 kinds of pesticide residue such as BHC in the mango are not detected; the content of heavy metal such as mercury and cadmium is 0.001-0.006 mg/kg. Then the quality and quality safety indicators of organic mango are discussed, and finally the Guangxi local standards of organic mango products are developed. 展开更多
关键词 organIC MANGO PRODUCTION measures QUALITY sAFETY s
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