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Chinese Company Doubles as “Mother” of Orphans
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作者 JU JIUJIANG & WANG GUILAN 《The Journal of Human Rights》 2011年第5期15-16,共2页
The story goes back to the end of 2007, when Yang Min, Party secretary and deputy chief manager of theNantong Times Clothing Co., Ltd. in Rugao, Jiangsu Province, heard what had happened to an orphan in the city.
关键词 of Orphans Chinese Company doubles as CO MOTHER
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Fair Scheduling Models for Doubles Group Competitions
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作者 Vardges Melkonian 《American Journal of Operations Research》 2021年第6期338-356,共19页
This paper gives integer linear programming models for scheduling doubles tennis group competitions. The goal is to build a fair and competitive schedule for all players. Our basic model achieves that for each player ... This paper gives integer linear programming models for scheduling doubles tennis group competitions. The goal is to build a fair and competitive schedule for all players. Our basic model achieves that for each player the average ranking of his partners in all matches is as close as possible to the average ranking of his opponents in all matches. One of the variations of the basic model provides that each matchup is fair and competitive. We also give models for the case when the number of players is 4n<span style="font-family:;" "=""> </span><span style="font-family:;" "="">+</span><span style="font-family:;" "=""> </span><span style="font-family:;" "="">2, and thus one of the matches has to be singles. Our models were implemented and tested using optimization software AMPL. Computational results along with schedules for some typical situations are also given the paper.</span> 展开更多
关键词 Sport Scheduling doubles Tournaments Optimization Modeling Integer Linear Programming
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DoubleSeal SuperShorty密封盖
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《印刷技术》 2012年第2期61-61,共1页
Bericap公司新推出了一款Doubel SealSuperShorty密封盖(如图9所示),该密封盖采用了特有的DoubleSeal技术,将内外密封合二为一,
关键词 doubleseal公司 印刷技术 印刷质量 SuperShorty密封盖
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Numerical simulation of dynamic thermal process during doublesided asymmetrical TIG backing welding of large thick plates 被引量:2
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作者 刘殿宝 赵慧慧 +2 位作者 李福泉 张广军 吴林 《China Welding》 EI CAS 2011年第1期44-48,共5页
The dynamic thermal process during double-sided asymmetrical TIG backing welding of large thick plates ( 1 000 mm×700 mm×50 mm) is numerically simulated using MSC. MARC. The effect of arc distance on the t... The dynamic thermal process during double-sided asymmetrical TIG backing welding of large thick plates ( 1 000 mm×700 mm×50 mm) is numerically simulated using MSC. MARC. The effect of arc distance on the thermal cycle in weld zone during double-sided asymmetrical T1G backing welding is investigated. The results show that the workpiece experiences double-peak thermal cycle in double-sided asymmetrical TIG backing welding. On the one hand, the fore arc has the pre- heating effect on the rear pass, and the pre-heating temperature depends on the distance between the double arcs, the heat input of fore arc, and the initial temperature of workpiece. On the other hand, the rear arc has the post-heating effect on the fore pass. The mutual effects of two heat sources decrease with the increase of arc distance. 展开更多
关键词 numerical simulation double-sided asymmetrical TIG backing welding thermal process double heat sources on double sides
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On the structure and representations of non-balanced quantum doubles
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作者 CHEN Li-li LI Fang 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2012年第4期475-488,共14页
For a field k and two finite groups G and X, when G acts on X from the right by group automorphisms, there is a Hopf algebra structure on k-space (kX°P)* kG (see Theorem 2.1), called a non-balanced quantum ... For a field k and two finite groups G and X, when G acts on X from the right by group automorphisms, there is a Hopf algebra structure on k-space (kX°P)* kG (see Theorem 2.1), called a non-balanced quantum double and denoted by Dx(G). In this paper, some Hopf algebra properties of Dx (G) are given, the representation types of Dx (G) viewed as a k-algebra are discussed, the algebra structure and module category over Dx(G) are studied. Since the Hopf algebra structure of non-balanced quantum double DX (G) generMizes the usual quantum double D(G) for a finite group G, all results about Dx(G) in this paper can also be used to describe D(G) as a special case and the universal R-matrix of Dx (G) provides more solutions of Yang-Baxter equation. 展开更多
关键词 non-balanced quantum double Hopf Mgebra representation type quasi-triangularity quiver.
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Discovery of primary lung cancer following resection of rectal cancer lung metastasis:A case report
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作者 Fei-Yan Zhou Fang-Hua Song +1 位作者 Zhen-Hao Cheng Sen Wu 《World Journal of Clinical Oncology》 2025年第2期173-179,共7页
BACKGROUND Colorectal cancer(CRC)ranks high among the most common types of malignant tumors.The primary cause of cancer-related mortality is metastasis,with lung metastases accounting for 32.9%of all cases of metastat... BACKGROUND Colorectal cancer(CRC)ranks high among the most common types of malignant tumors.The primary cause of cancer-related mortality is metastasis,with lung metastases accounting for 32.9%of all cases of metastatic CRC(MCRC).However,cases of MCRC in the lungs,which present concurrently with primary peripheral lung adenocarcinoma,are exceptionally rare.CASE SUMMARY This report describes the case of a 52-year-old female patient who,following a colonoscopy,was diagnosed with moderately differentiated adenocarcinoma based on rectal mucosal biopsy findings.A preoperative chest computed tomography scan revealed a ground-glass nodule in the right lung and a small nodule(approximately 0.6 cm in diameter)in the extramural basal segment of the left lower lobe,which suggested multiple lung metastases from rectal cancer.Subsequent treatment and follow-up led to a diagnosis of rectal cancer with left lung metastasis and peripheral adenocarcinoma of the lower lobe of the right lung.CONCLUSION This case report describes the therapeutic journey of a patient with lung metastasis from rectal cancer in addition to primary peripheral adenocarcinoma,thus underscoring the critical roles of multidisciplinary collaboration,personalized treatment strategies,and comprehensive patient rehabilitation guidance. 展开更多
关键词 Rectal cancer Metastatic lung cancer Peripheral lung adenocarcinoma Double primary cancer Case report
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Proof of the Volume Conjecture for Whitehead Doubles of a Family of Torus Knots
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作者 Hao ZHENG 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2007年第4期375-388,共14页
A technique to compute the colored Jones polynomials of satellite knots, illustrated by the Whitehead doubles of knots, is presented. Then the author proves the volume conjecture for Whitehead doubles of a family of t... A technique to compute the colored Jones polynomials of satellite knots, illustrated by the Whitehead doubles of knots, is presented. Then the author proves the volume conjecture for Whitehead doubles of a family of torus knots and shows some interesting observations. 展开更多
关键词 Volume conjecture Whitehead double Torus knots Whitehead link
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Novel interface engineering of LDH-based materials on Mg alloy for efficient photocatalytic systems considering the geometrical linearity of condensed phosphates 被引量:3
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作者 Mosab Kaseem Ananda Repycha Safira Arash Fattah-alhosseini 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第1期267-280,共14页
This study presents a facile and rapid method for synthesizing novel Layered Double Hydroxide(LDH)nanoflakes,exploring their application as a photocatalyst,and investigating the influence of condensed phosphates'g... This study presents a facile and rapid method for synthesizing novel Layered Double Hydroxide(LDH)nanoflakes,exploring their application as a photocatalyst,and investigating the influence of condensed phosphates'geometric linearity on their photocatalytic properties.Herein,the Mg O film,obtained by plasma electrolysis of AZ31 Mg alloys,was modified by growing an LDH film,which was further functionalized using cyclic sodium hexametaphosphate(CP)and linear sodium tripolyphosphate(LP).CP acted as an enhancer for flake spacing within the LDH structure,while LP changed flake dispersion and orientation.Consequently,CP@LDH demonstrated exceptional efficiency in heterogeneous photocatalysis,effectively degrading organic dyes like Methylene blue(MB),Congo red(CR),and Methyl orange(MO).The unique cyclic structure of CP likely enhances surface reactions and improves the catalyst's interaction with dye molecules.Furthermore,the condensed phosphate structure contributes to a higher surface area and reactivity in CP@LDH,leading to its superior photocatalytic performance compared to LP@LDH.Specifically,LP@LDH demonstrated notable degradation efficiencies of 93.02%,92.89%,and 88.81%for MB,MO,and CR respectively,over a 40 min duration.The highest degradation efficiencies were observed in the case of the CP@LDH sample,reporting 99.99%for MB,98.88%for CR,and 99.70%for MO.This underscores the potential of CP@LDH as a highly effective photocatalyst for organic dye degradation,offering promising prospects for environmental remediation and water detoxification applications. 展开更多
关键词 Plasma electrolysis Layered Double Hydroxide Condensed phosphates Adsorption capacity Photocatalytic efficiency
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Influence of variable viscosity and double diffusion on the convective stability of a nanofluid flow in an inclined porous channel 被引量:1
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作者 N.HUMNEKAR D.SRINIVASACHARYA 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第3期563-580,共18页
The influence of variable viscosity and double diffusion on the convective stability of a nanofluid flow in an inclined porous channel is investigated.The DarcyBrinkman model is used to characterize the fluid flow dyn... The influence of variable viscosity and double diffusion on the convective stability of a nanofluid flow in an inclined porous channel is investigated.The DarcyBrinkman model is used to characterize the fluid flow dynamics in porous materials.The analytical solutions are obtained for the unidirectional and completely developed flow.Based on a normal mode analysis,the generalized eigenvalue problem under a perturbed state is solved.The eigenvalue problem is then solved by the spectral method.Finally,the critical Rayleigh number with the corresponding wavenumber is evaluated at the assigned values of the other flow-governing parameters.The results show that increasing the Darcy number,the Lewis number,the Dufour parameter,or the Soret parameter increases the stability of the system,whereas increasing the inclination angle of the channel destabilizes the flow.Besides,the flow is the most unstable when the channel is vertically oriented. 展开更多
关键词 NANOFLUID inclined channel variable viscosity linear stability double dif-fusion porous medium
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基于Dueling Double DQN的交通信号控制方法
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作者 叶宝林 陈栋 +2 位作者 刘春元 陈滨 吴维敏 《计算机测量与控制》 2024年第7期154-161,共8页
为了提高交叉口通行效率缓解交通拥堵,深入挖掘交通状态信息中所包含的深层次隐含特征信息,提出了一种基于Dueling Double DQN(D3QN)的单交叉口交通信号控制方法;构建了一个基于深度强化学习Double DQN(DDQN)的交通信号控制模型,对动作... 为了提高交叉口通行效率缓解交通拥堵,深入挖掘交通状态信息中所包含的深层次隐含特征信息,提出了一种基于Dueling Double DQN(D3QN)的单交叉口交通信号控制方法;构建了一个基于深度强化学习Double DQN(DDQN)的交通信号控制模型,对动作-价值函数的估计值和目标值迭代运算过程进行了优化,克服基于深度强化学习DQN的交通信号控制模型存在收敛速度慢的问题;设计了一个新的Dueling Network解耦交通状态和相位动作的价值,增强Double DQN(DDQN)提取深层次特征信息的能力;基于微观仿真平台SUMO搭建了一个单交叉口模拟仿真框架和环境,开展仿真测试;仿真测试结果表明,与传统交通信号控制方法和基于深度强化学习DQN的交通信号控制方法相比,所提方法能够有效减少车辆平均等待时间、车辆平均排队长度和车辆平均停车次数,明显提升交叉口通行效率。 展开更多
关键词 交通信号控制 深度强化学习 Dueling Double DQN Dueling Network
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基于softmax的加权Double Q-Learning算法
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作者 钟雨昂 袁伟伟 关东海 《计算机科学》 CSCD 北大核心 2024年第S01期46-50,共5页
强化学习作为机器学习的一个分支,用于描述和解决智能体在与环境的交互过程中,通过学习策略以达成回报最大化的问题。Q-Learning作为无模型强化学习的经典方法,存在过估计引起的最大化偏差问题,并且在环境中奖励存在噪声时表现不佳。Dou... 强化学习作为机器学习的一个分支,用于描述和解决智能体在与环境的交互过程中,通过学习策略以达成回报最大化的问题。Q-Learning作为无模型强化学习的经典方法,存在过估计引起的最大化偏差问题,并且在环境中奖励存在噪声时表现不佳。Double Q-Learning(DQL)的出现解决了过估计问题,但同时造成了低估问题。为解决以上算法的高低估问题,提出了基于softmax的加权Q-Learning算法,并将其与DQL相结合,提出了一种新的基于softmax的加权Double Q-Learning算法(WDQL-Softmax)。该算法基于加权双估计器的构造,对样本期望值进行softmax操作得到权重,使用权重估计动作价值,有效平衡对动作价值的高估和低估问题,使估计值更加接近理论值。实验结果表明,在离散动作空间中,相比于Q-Learning算法、DQL算法和WDQL算法,WDQL-Softmax算法的收敛速度更快且估计值与理论值的误差更小。 展开更多
关键词 强化学习 Q-LEARNING Double Q-Learning Softmax
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Enabling an Inorganic-Rich Interface via Cationic Surfactant for High-Performance Lithium Metal Batteries 被引量:1
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作者 Zejun Sun Jinlin Yang +18 位作者 Hongfei Xu Chonglai Jiang Yuxiang Niu Xu Lian Yuan Liu Ruiqi Su Dayu Liu Yu Long Meng Wang Jingyu Mao Haotian Yang Baihua Cui Yukun Xiao Ganwen Chen Qi Zhang Zhenxiang Xing Jisheng Pan Gang Wu Wei Chen 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第8期1-17,共17页
An anion-rich electric double layer(EDL)region is favorable for fabricating an inorganic-rich solid-electrolyte interphase(SEI)towards stable lithium metal anode in ester electrolyte.Herein,cetyltrimethylammonium brom... An anion-rich electric double layer(EDL)region is favorable for fabricating an inorganic-rich solid-electrolyte interphase(SEI)towards stable lithium metal anode in ester electrolyte.Herein,cetyltrimethylammonium bromide(CTAB),a cationic surfactant,is adopted to draw more anions into EDL by ionic interactions that shield the repelling force on anions during lithium plating.In situ electrochemical surface-enhanced Raman spectroscopy results combined with molecular dynamics simulations validate the enrichment of NO_(3)^(−)/FSI−anions in the EDL region due to the positively charged CTA^(+).In-depth analysis of SEI structure by X-ray photoelectron spectroscopy and time-of-flight secondary ion mass spectrometry results confirmed the formation of the inorganic-rich SEI,which helps improve the kinetics of Li^(+)transfer,lower the charge transfer activation energy,and homogenize Li deposition.As a result,the Li||Li symmetric cell in the designed electrolyte displays a prolongated cycling time from 500 to 1300 h compared to that in the blank electrolyte at 0.5 mA cm^(-2) with a capacity of 1 mAh cm^(-2).Moreover,Li||LiFePO_(4) and Li||LiCoO_(2) with a high cathode mass loading of>10 mg cm^(-2) can be stably cycled over 180 cycles. 展开更多
关键词 Cationic surfactant Lithium nitrate additive Solid-electrolyte interphase Electric double layer Lithium metal batteries
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Enhancing the stability of Ni Fe-layered double hydroxide nanosheet array for alkaline seawater oxidation by Ce doping 被引量:1
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作者 Yongchao Yao Shengjun Sun +14 位作者 Hui Zhang Zixiao Li Chaoxin Yang Zhengwei Cai Xun He Kai Dong Yonglan Luo Yan Wang Yuchun Ren Qian Liu Dongdong Zheng Weihua Zhuang Bo Tang Xuping Sun Wenchuang(Walter)Hu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第4期306-312,共7页
Electrocatalytic hydrogen production from seawater holds enormous promise for clean energy generation.Nevertheless,the direct electrolysis of seawater encounters significant challenges due to poor anodic stability cau... Electrocatalytic hydrogen production from seawater holds enormous promise for clean energy generation.Nevertheless,the direct electrolysis of seawater encounters significant challenges due to poor anodic stability caused by detrimental chlorine chemistry.Herein,we present our recent discovery that the incorporation of Ce into Ni Fe layered double hydroxide nanosheet array on Ni foam(Ce-Ni Fe LDH/NF)emerges as a robust electrocatalyst for seawater oxidation.During the seawater oxidation process,CeO_(2)is generated,effectively repelling Cl^(-)and inhibiting the formation of Cl O-,resulting in a notable enhancement in the oxidation activity and stability of alkaline seawater.The prepared Ce-Ni Fe LDH/NF requires only overpotential of 390 m V to achieve the current density of 1 A cm^(-2),while maintaining long-term stability for 500 h,outperforming the performance of Ni Fe LDH/NF(430 m V,150 h)by a significant margin.This study highlights the effectiveness of a Ce-doping strategy in augmenting the activity and stability of materials based on Ni Fe LDH in seawater electrolysis for oxygen evolution. 展开更多
关键词 Ce doping NiFe layered double hydroxide Seawater oxidation Electrocatalysis Cl^(-) repulsion
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Double contrast-enhanced ultrasonography improves diagnostic accuracy of T staging compared with multi-detector computed tomography in gastric cancer patients 被引量:1
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作者 Yan-Fen Xu Hui-Yun Ma +4 位作者 Gui-Ling Huang Yu-Ting Zhang Xue-Yan Wang Ming-Jie Wei Xiao-Qing Pei 《World Journal of Gastroenterology》 SCIE CAS 2024年第23期3005-3015,共11页
BACKGROUND Gastric cancer(GC)is the most common malignant tumor and ranks third for cancer-related deaths among the worldwide.The disease poses a serious public health problem in China,ranking fifth for incidence and ... BACKGROUND Gastric cancer(GC)is the most common malignant tumor and ranks third for cancer-related deaths among the worldwide.The disease poses a serious public health problem in China,ranking fifth for incidence and third for mortality.Knowledge of the invasive depth of the tumor is vital to treatment decisions.AIM To evaluate the diagnostic performance of double contrast-enhanced ultrasonography(DCEUS)for preoperative T staging in patients with GC by comparing with multi-detector computed tomography(MDCT).METHODS This single prospective study enrolled patients with GC confirmed by preoperative gastroscopy from July 2021 to March 2023.Patients underwent DCEUS,including ultrasonography(US)and intravenous contrast-enhanced ultrasonography(CEUS),and MDCT examinations for the assessment of preoperative T staging.Features of GC were identified on DCEUS and criteria developed to evaluate T staging according to the 8th edition of AJCC cancer staging manual.The diagnostic performance of DCEUS was evaluated by comparing it with that of MDCT and surgical-pathological findings were considered as the gold standard.RESULTS A total of 229 patients with GC(80 T1,33 T2,59 T3 and 57 T4)were included.Overall accuracies were 86.9%for DCEUS and 61.1%for MDCT(P<0.001).DCEUS was superior to MDCT for T1(92.5%vs 70.0%,P<0.001),T2(72.7%vs 51.5%,P=0.041),T3(86.4%vs 45.8%,P<0.001)and T4(87.7%vs 70.2%,P=0.022)staging of GC.CONCLUSION DCEUS improved the diagnostic accuracy of preoperative T staging in patients with GC compared with MDCT,and constitutes a promising imaging modality for preoperative evaluation of GC to aid individualized treatment decision-making. 展开更多
关键词 Double contrast-enhanced ultrasonography Multi-detector computed tomography Gastric cancer T staging
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与第三类潘勒韦方程相关的广义代数微分方程的亚纯解 被引量:1
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作者 古勇毅 张欣茹 孔荫莹 《工程数学学报》 CSCD 北大核心 2024年第4期757-768,共12页
潘勒韦方程是典型的非线性微分方程,应用广泛。复方法结合了复分析和微分方程理论,是求解非线性微分方程亚纯解的有效方法。利用复方法证明了与第三类潘勒韦方程相关的广义代数微分方程的亚纯解属于W类,并得到了该方程的亚纯解。通过适... 潘勒韦方程是典型的非线性微分方程,应用广泛。复方法结合了复分析和微分方程理论,是求解非线性微分方程亚纯解的有效方法。利用复方法证明了与第三类潘勒韦方程相关的广义代数微分方程的亚纯解属于W类,并得到了该方程的亚纯解。通过适当的变换以及应用所得的结果,得到了修正的double sine-Gordon方程和修正的Kortweg-de-Vries(mKdV)方程的W类亚纯精确解,并得到了相关非线性偏微分方程的非W类亚纯精确解。众所周知,使用基于行波变换等变换以及与第三类潘勒韦方程相关的广义代数微分方程的亚纯解,便于寻求其他相关的数学物理方程的亚纯精确解。在今后的工作中,可进一步对其他类别的潘勒韦方程相关的广义代数微分方程的亚纯解及应用进行研究。 展开更多
关键词 微分方程 潘勒韦方程 修正的double sine-Gordon方程 MKDV方程 亚纯函数
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Exploring the Dual Subjectivity of Kindergarten's Self-made Play and Teaching Aids Activities from the Perspective of Children's Play Development in China 被引量:1
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作者 Yuwei Zhao 《教育技术与创新》 2024年第1期1-9,共9页
The joint development of teachers and young children is the basis for promoting the development of high-quality preschool education in the new era,and encouraging early childhood teachers to make playthings according ... The joint development of teachers and young children is the basis for promoting the development of high-quality preschool education in the new era,and encouraging early childhood teachers to make playthings according to local conditions is both the fine tradition of China's early childhood education and the direct orientation of China's preschool education policy.Homemade play and teaching aids are some of the methods often used in kindergartens,which skillfully combine young children's daily life objects with toys and early childhood teaching,not only enriching the collective activities of young children but also cultivating children's abilities in various aspects.Kindergarten homemade"play and teaching aids"for early childhood teachers and children have their special educational significance and value,therefore,this paper is based on the children and teachers double subject basis,discussing the homemade"play and teaching aids"for children and teachers of the double subject meanings,and puts forward the realization of the This paper discusses the double-subjective meaning of homemade teaching aids for children and teachers on the basis of the double-subjective foundation of children and teachers,and puts forward specific suggestions for realizing the double-subjectivity of kindergarten homemade teaching aids to enrich the theoretical value and practical significance of homemade teaching aids,to provide theoretical references and support for the relevant staff. 展开更多
关键词 Self-made playthings Double subjectivity KINDERGARTEN China
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Deprotonated of layered double hydroxides during electrocatalytic water oxidation for multi-cations intercalation 被引量:1
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作者 Bowen Jin Jianxiong Gao +1 位作者 Yunqi Zhang Mingfei Shao 《Smart Molecules》 2024年第2期1-14,共14页
Aqueous rechargeable batteries using abundant multi-ion cations have receivedincreasing attention in the energy storage field for their high safety and low cost.Layered double hydroxides(LDHs)possess a two-dimensional... Aqueous rechargeable batteries using abundant multi-ion cations have receivedincreasing attention in the energy storage field for their high safety and low cost.Layered double hydroxides(LDHs)possess a two-dimensional structure andexhibit great potential as cathodes for multi-ion intercalation.However,theinsufficient active sites of LDHs result in low capacities in the discharging process.Interestingly,the LDHs after the deprotonation process exhibit favorable electrochemicalperformance of multi-cation intercalation.The deprotonation process ofLDHs has been widely found in the oxygen evolution reaction and energy storagefield,where LDHs lose H in laminates and converts to deprotonatedγ-phaseMOOHs(MOOs).Herein,we take a comprehensive overview of the dynamicsstructure transformation of the deprotonation process of LDHs.Furthermore,thedevelopment of advanced aqueous battery cathode and metal battery anode basedon deprotonated LDHs for energy storage is explored and summarized.Finally,theperspective of deprotonated LDHs in the energy storage field is discussed. 展开更多
关键词 DEPROTONATION energy storage layered double hydroxides multi-ion battery
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Defective Nickel-Iron Layered Double Hydroxide for Enhanced Photocatalytic NO Oxidation with Significant Alleviation of NO2 Production
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作者 Xiaoyu Li Xiaoshu Lv +6 位作者 Jian Pan Peng Chen Huihui Peng Yan Jiang Haifeng Gong Guangming Jiang Li’an Hou 《Engineering》 SCIE EI CAS CSCD 2024年第5期276-284,共9页
Photocatalysis offers a sustainable means for the oxidative removal of low concentrations of NOx(NO,NO2,N2O,N2O5,etc.)from the atmosphere.Layered double hydroxides(LDHs)are promising candidate photocatalysts owing to ... Photocatalysis offers a sustainable means for the oxidative removal of low concentrations of NOx(NO,NO2,N2O,N2O5,etc.)from the atmosphere.Layered double hydroxides(LDHs)are promising candidate photocatalysts owing to their unique layered and tunable chemical structures and abundant surface hydroxide(OH)moieties,which are hydroxyl radical(OH)precursors.However,the practical applications of LDHs are limited by their poor charge-separation ability and insufficient active sites.Herein,we developed a facile N_(2)H_(4)-driven etching approach to introduce dual Ni^(2+)and OHvacancies(Niv and OHv,respectively)into NiFe-LDH nanosheets(hereafter referred to as NiFe-LDH-et)to facilitate improved charge-carrier separation and active Lewis acidic site(Fe^(3+)and Ni^(2+)exposed at OHv)formation.In contrast to inert pristine LDH,NiFe-LDH-et actively removed NO under visible-light illumination.Specifically,Ni_(76)Fe_(24)-LDH-et etched with 1.50 mmol·L^(-1)N_(2)H_(4)solution removed 32.8%of the NO in continuously flowing air(NO feed concentration:500 parts per billion(ppb))under visible-light illumination,thereby outperforming most reported catalysts.Experimental and theoretical data revealed that the dual vacancies promoted the production of reactive oxygen species(O_(2)·^(-)andOH)and the adsorption of NO on the LDH.In situ spectroscopy demonstrated that NO was preferentially adsorbed at Lewis acidic sites,particularly exposed Fe^(3+)sites,converted into NO+,and subsequently oxidized to NO3without the notable formation of the more toxic intermediate NO2,thereby alleviating risks associated with its production and emission. 展开更多
关键词 Vacancie Layered double hydroxide NO+ PHOTOCATALYSIS NO removal
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Flexibility potential of Cs_(2)BX_(6)(B=Hf,Sn,Pt,Zr,Ti;X=I,Br,Cl)with application in photovoltaic devices and radiation detectors
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作者 Songya Wang Changcheng Chen +11 位作者 Shaohang Shi Ziyi Zhang Yan Cai Shuli Gao Wen Chen Shuangna Guo Elyas Abduryim Chao Dong Xiaoning Guan Ying Liu Gang Liu Pengfei Lu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第8期271-287,I0006,共18页
As interest in double perovskites is growing,especially in applications like photovoltaic devices,understanding their mechanical properties is vital for device durability.Despite extensive exploration of structure and... As interest in double perovskites is growing,especially in applications like photovoltaic devices,understanding their mechanical properties is vital for device durability.Despite extensive exploration of structure and optical properties,research on mechanical aspects is limited.This article builds a vacancyordered double perovskite model,employing first-principles calculations to analyze mechanical,bonding,electronic,and optical properties.Results show Cs_(2)Hfl_(6),Cs_(2)SnBr_(6),Cs_(2)SnI_(6),and Cs_(2)PtBr_(6)have Young's moduli below 13 GPa,indicating flexibility.Geometric parameters explain flexibility variations with the changes of B and X site composition.Bonding characteristic exploration reveals the influence of B and X site electronegativity on mechanical strength.Cs_(2)SnBr_(6)and Cs_(2)PtBr_(6)are suitable for solar cells,while Cs_(2)HfI_(6)and Cs_(2)TiCl_(6)show potential for semi-transparent solar cells.Optical property calculations highlight the high light absorption coefficients of up to 3.5×10^(5) cm^(-1)for Cs_(2)HfI_(6)and Cs_(2)TiCl_(6).Solar cell simulation shows Cs_(2)PtBr_(6)achieves 22.4%of conversion effciency.Cs_(2)ZrCl_(6)holds promise for ionizing radiation detection with its 3.68 eV bandgap and high absorption coefficient.Vacancy-ordered double perovskites offer superior flexibility,providing valuable insights for designing stable and flexible devices.This understanding enhances the development of functional devices based on these perovskites,especially for applications requiring high stability and flexibility. 展开更多
关键词 Double perovskite Mechanical properties Flexible PHOTOVOLTAIC Radiation detectors
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Vitamin and zeatin treatments promote colchicine-induced haploid chromosome doubling in maize
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作者 Chen Chen Yuling Zhang +4 位作者 Chenxu Liu Jinlong Li Jiuran Zhao Yuandong Wang Shaojiang Chen 《The Crop Journal》 SCIE CSCD 2024年第6期1677-1685,共9页
Doubled haploid(DH)technology is an efficient method used in commercial maize breeding.Chromosome doubling is a vital step of DH technology;however,the underlying processes regulating chromosome doubling of haploid is... Doubled haploid(DH)technology is an efficient method used in commercial maize breeding.Chromosome doubling is a vital step of DH technology;however,the underlying processes regulating chromosome doubling of haploid is still not well understood,which is key to optimize the technology.In this study,the immature haploid embryos of the maize inbred line Zheng58 treated with amiprophos-methyl(APM)or colchicine were used to analyze transcriptomic and metabolomic changes,75 and 60 differential expressed metabolites(DEMs)were identified between control treatment,respectively.Most differentially expressed genes(DEGs)related to artificial chromosome doubling were down regulated;these were mainly involved in mitosis process.Both DEMs and DEGs co-expression analyses showed that,compared to controls,zeatin biosynthesis and cofactor and vitamin metabolism were significantly enriched in both APM and colchicine treatments.In a parallel experiment,exogenous vitamins including thiamine,nicotinic acid,vitamin B6,or trans-zeatin were added to colchicine treatment;there were synergistic effects between vitamins or zeatin and colchicine in haploid artificial chromosome doubling.These results provide novel insights in exploring the molecular responses to antimitotic reagents at both the transcriptomic and metabolomic levels.In addition,the application efficiency of haploid breeding will be greatly improved by the key factors for artificial chromosome doubling. 展开更多
关键词 Antimitotic reagent Artificial chromosome doubling TRANSCRIPTOMIC Metabolomic MAIZE
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