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Nano Research 2024年第9期17卷 8552-8559页

作者： Donghao Zhang Lianxi Si Qianqian ren Xintong Yan Shi Hu Department of Chemistry School of ScienceTianjin Key Laboratory of Molecular Optoelectronic ScienceTianjin UniversityTianjin 300072China

Pd-based catalysts exhibit higher catalytic activity and durability in many electrochemical ***,the electrochemical performance can be further enhanced by fine-tune of the alloy *** binary alloys have been fully studied,the multicomponent alloys are far beyond understanding,which leaves cocktail effect a compromised explanation for the high-entropy *** Pd nanosheet-seeded growth was used to synthesize a Pd-Zn-Cd ternary alloy by accurately controlling the Pd-Zn-Cd molar ratio through adjusting the amount of introduced Cd *** analysis of the crystal phase structure of PdCdZnx and PdZn_(x)Cd_(1-x),the competitive relationship of Zn and Cd in the alloying process with Pd was unveiled:Pd1Cd1 intermetallics(IMC)is thermodynamically favored over Pd_(1)Zn_(1)IMC in the ternary ***,the increased structure stability of PdCd over PdZn does not bring about increased durability in the catalytic ethanol oxidation *** morphology selection of Pd seeds is also crucial for the study,as Pd cubes,Pd tetrahedrons,and Pd octahedrons do not form PdZn in the same *** successful alloying through the seeded growth depends on the maximum diffusion depth of foreign atoms into the seed.

关键词： PdZn alloy seed growth method ethanol oxidation reaction composition control ternary alloying

The impact of demographic dynamics on food consumption and its environmental outcomes:Evidence from China

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Journal of Integrative Agriculture 2024年第2期23卷 414-429页

作者： Shaoting Li Xuan Chen Yanjun ren Thomas Glauben College of Economics and Management Northwest A&F UniversityYangling 712100China Leibniz Institute of Agricultural Development in Transition Economies(IAMO) Halle(Saale)06120Germany Sino-German Center for Agricultural and Food Economics Northwest A&F UniversityYangling 712100China

With increasing population and changing demographics,food consumption has experienced a significant transition in quantity and ***,a dearth of knowledge remains regarding its environmental impacts and how it responds to demographic dynamics,particularly in emerging economies like *** the two-stage Quadratic Almost Demand System(QUAIDS)model,this study empirically examines the impact of demographic dynamics on food consumption and its environmental outcomes based on the provincial data from 2000 to 2020 in *** various scenarios,according to changes in demographics,we extend our analysis to project the long-term trend of food consumption and its environmental impacts,including greenhouse gas(GHG)emissions,water footprint(WF),and land appropriation(LA).The results reveal that an increase in the proportion of senior people significantly decreases the consumption of grain and livestock meat and increases the consumption of poultry,egg,and aquatic products,particularly for urban ***,an increase in the proportion of males in the population leads to higher consumption of poultry and aquatic ***,in the current scenario of an increased aging population and sex ratio,it is anticipated that GHG emissions,WF,and LA are likely to decrease by 1.37,2.52,and 3.56%,*** importantly,in the scenario adhering to the standards of nutritional intake according to the Dietary Guidelines for Chinese Residents in 2022,GHG emissions,WF,and LA in urban areas would increase by 12.78,20.94,and 18.32%,*** findings suggest that changing demographics should be considered when designing policies to mitigate the diet-environment-health trilemma and achieve sustainable food consumption.

关键词： demographic dynamics food consumption environmental impacts nutrition intakes

Prescribed time control based on the periodic delayed sliding mode surface without singularities

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Science China(Information Sciences) 2024年第7期67卷 256-270页

作者： Bin ZHOU Yi DING Kang-Kang ZHANG Guang-ren DUAN Center for Control Theory and Guidance Technology Harbin Institute of Technology

In this paper, nonsingular prescribed-time control is studied based on periodic delayed sliding mode surfaces. Different from the existing sliding mode control, where either singularity problems may appear or the convergence time depends on the initial state, the proposed sliding mode control approaches can achieve prescribed-time convergence without singularity. The proposed nonsingular sliding mode control approaches can be applied to both second-order and high-order nonlinear systems with prescribed-time convergence. As applications of the proposed sliding mode control approaches, the control of hypersonic vehicle systems is revisited. Numerical simulations on the nonlinear model of the hypersonic vehicle system show the effectiveness of the proposed methods.

关键词： prescribed-time control smooth periodic delayed feedback sliding mode control high-order nonlinear systems hypersonic vehicle systems

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A model reduction approach for discrete-time linear time-variant systems with delayed inputs

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Science China(Information Sciences) 2024年第4期67卷 197-217页

作者： Ai-Guo WU Guang-ren DUAN Yu WANG Jie ZHANG School of Mechanical Engineering and Automation Harbin Institute of Technology(Shenzhen) HIT Wuhu Robot Technology Research Institute Center for Control Science and Technology Southern University of Science and Technology

A model reduction approach is presented for discrete-time linear time-variant input-delayed systems. According to this proposed approach, a dynamical variable is constructed by taking advantage of the current state and historical information of input. It is revealed that the behavior of this dynamical variable is governed by a discrete-time linear delay-free system. It is worth noting that the presented variable transformation does not require the system matrix to be invertible. Based on the reduced delay-free models,stabilizing control laws can be easily obtained for the original delayed system. For the case with a single input delay, the constructed variable is an exact prediction for the future state, and thus the stabilizing control law could be designed by replacing the future state with its prediction. Finally, three discrete-time periodic systems with delayed input are employed to illustrate how to utilize the presented model reduction approaches.

关键词： reduction approach predictor-based feedback time-varying systems delayed input periodic system

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High-throughput and simultaneous inertial separation of tumor cells and clusters from malignant effusions using spiral-contraction-expansion channels

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Microsystems & Nanoengineering 2024年第2期10卷 91-99页

作者： Zhixian Zhu Hui ren Dan Wu Zhonghua Ni Nan Xiang School of Mechanical Engineering and Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical InstrumentsSoutheast University211189NanjingChina School of Mechanical Technology Wuxi Institute of TechnologyNo.1600 Gaolang West Road214129WuxiChina Department of Oncology Jiangyin People’s Hospital214400JiangyinChina

Tumor cell clusters are regarded as critical factors in cancer pathophysiology,and increasing evidence of their higher treatment resistance and metastasis compared to single tumor cells has been ***,existing cell separation methods that are designed for single tumor cells cannot be used to simultaneously purify tumor cell *** address this problem,we demonstrated a microfluidic approach for the high-throughput,continuous-flow ternary separation of single tumor cells,tumor cell clusters,and WBCs from clinical pleural or abdominal effusions by coupling slanted spiral channels and periodic contraction-expansion *** first systematically explored the influence of particle size and flow rate on particle *** separation performance indicated that 94.0%of WBCs were removed and more than 97%of MDA-MB-231 tumor cells were recovered at a high flow rate of 3500µL/***,more than 90%of tumor cell clusters were effectively preserved after ***,we successfully applied our device for the ternary separation of single tumor cells,tumor cell clusters,and WBCs from different malignant effusions collected from patients with metastatic ***,our spiral-contraction-expansion device has potential as a sample pretreatment tool for the cytological diagnosis of malignant effusions.

关键词： separation contraction removed

Partition and planning:A human-like motion decision for UAV in trap environment

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Science China(Technological Sciences) 2024年第4期67卷 1226-1237页

作者： CHEN JinTao ZHOU Qi ren HongRu LI HongYi School of Automation Guangdong University of TechnologyGuangzhou 510006China Provincial Key Laboratory of Intelligent Decision and Cooperative Control Guangdong University of Technology Guangzhou 510006Chi

This paper presents a human-like motion decision-making method for unmanned aerial vehicles(UAVs)navigating in trap *** proposed a space partitioning method based on sampling and consistency control to conduct a preliminary analysis of the indoor environment based on architectural *** method reduces the dimensionality of the path planning problem,thereby enhancing the ***,we designed a target-switching logic for the dynamic window *** improvement endows the UAV with the capability of both real-time obstacle avoidance and global navigation,enhancing the efficiency of the UAV in flying to task spots ***,by applying human-like methods of batch distance perception and obstacle perception to this scheme,we have further enhanced the robustness and efficiency of path ***,considering the scenario of high-rise fire rescue,we conducted simulation *** demonstrates that our scheme enhances the efficiency and robustness of path planning.

关键词： path planning indoor environment spacial partition high-rise fire rescue

Nicotine up-regulates SLC7A5 expression depending on TRIM29 in non-small cell lung cancer

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Genes & Diseases 2024年第2期11卷 582-584页

作者： Dahua Liu Haolin ren Guimin Wen Pu Xia Biological Anthropology Institute College of Basic Medical ScienceJinzhou Medical UniversityJinzhouLiaoning 121000China Department of Radiology The First Affiliated Hospital of Dalian Medical UniversityDalianLiaoning 116011China Department of Community Nursing College of NursingJinzhou Medical UniversityJinzhouLiaoning 121000China

Non-small cell lung cancer(NSCLC)is a malignant tumor that poses a serious threat to human ***(LUAD)and squamous cell carcinoma(LUSC)are two common types of *** originate from glandular and squamous cells of the bronchial epithelium,*** gene changes during tumorigenesis is conducive to the selection of suitable treatment methods for ***98 is a heterodimeric transmembrane glycoprotein,which is composed of a heavy chain and a light chain.1 cD98 heavy chain(CD98hc),also known as 4F2hc or SLC3A2,is an 85kDa type ll transmembraneglycoprotein,which consists of a cytoplasmic region(NH2 terminal),a single chain transmembrane region,and a huge extracellular region(COOH terminal).1 CD98hc can combine with the CD98 light chain,LAT1(SLC7A5),to form CD98 protein through disulfide bonds.1 SLC7A5 is a 12 times transmembrane helix bundle protein composed of 501-535 amino acid residues1.

关键词： lung cancer NSCLC

Parameter-Free Shifted Laplacian Reconstruction for Multiple Kernel Clustering

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 1072-1074页

作者： Xi Wu Zhenwen ren F.Richard Yu the School of National Defence Science and Technology Southwest University of Science and TechnologyMianyang 621010China the School of National Defence Science and Technology Southwest University of Science and TechnologyMianyang 621010 the Guangxi Key Laboratory of Machine Vision and Intelligent Control Wuzhou UniversityWuzhou 543002 the Guangdong Laboratory of Artificial Intelligence and Digital Economy(SZ) Shenzhen 518060China

Dear Editor,This letter proposes a parameter-free multiple kernel clustering(MKC)method by using shifted Laplacian *** MKC can effectively cluster nonlinear data,but it faces two main challenges:1)As an unsupervised method,it is up against parameter problems which makes the parameters intractable to tune and is unfeasible in real-life applications;2)Only considers the clustering information,but ignores the interference of noise within Laplacian.

关键词： parameter letter Parameter

Design and optimization of a greener sinomenine hydrochloride preparation process considering variations among different batches of the medicinal herb

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Chinese Journal of Chemical Engineering 2024年第7期71卷 77-90页

作者： Dandan ren Jiale Xie Tianle Chen Haibin Qu Xingchu Gong Pharmaceutical Informatics Institute College of Pharmaceutical SciencesZhejiang UniversityHangzhou 310058China National Key Laboratory of Chinese Medicine Modernization Zhejiang UniversityHangzhou 310058China Jinhua Institute of Zhejiang University Jinhua 321016China

The current methods used to industrially produce sinomenine hydrochloride involve several issues,including high solvent toxicity,long process flow,and low atomic utilization efficiency,and the greenness scores of the processes are below 65 *** solve these problems,a new process using anisole as the extractant was *** exhibits high selectivity for sinomenine and can be connected to the subsequent water-washing *** alkalization of the medicinal material,heating extraction,water washing,and acidification crystallization were carried *** process was modeled and *** design space was *** recommended operating ranges for the critical process parameters were 3.0–4.0 h for alkalization time,60.0–80.0℃ for extraction temperature,2.0–3.0(volume ratio)for washing solution amount,and 2.0–2.4 mol·L^(-1) for hydrochloric acid *** new process shows good robustness because different batches of medicinal materials did not greatly impact crystal purity or sinomenine transfer *** sinomenine transfer rate was about 20%higher than that of industrial *** greenness score increased to 90 points since the novel process proposed in this research solves the problems of long process flow,high solvent toxicity,and poor atomic economy,better aligning with the concept of green chemistry.

关键词： Sinomenine hydrochloride Process optimization Anisole

A convenient method for measuring gas-liquid volumetric mass transfer coefficient in micro reactors

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Chinese Chemical Letters 2024年第4期35卷 389-392页

作者： Haoyang Wang Ronghao Zhang Yanlun ren Li Zhang School of Mechanical and Power Engineering East China University of Science and TechnologyShanghai 200237China

The research on gas-liquid multiphase reactions using micro reactors is becoming increasingly widespread, given their excellent mass transfer performance. Establishing an accurate and reliable method to measure the gas-liquid mass transfer performance of micro reactors is crucial for evaluating and optimizing the design of micro reactor structure. In this paper, the physical absorption method of aqueous solution-CO_(2) and the chemical absorption method of sodium carbonate solution-CO_(2) were proposed. By analyzing the chemical reaction equilibrium during the absorption process, the relationship between the mass transfer of CO_(2) and the solubility of hydroxide ions in the solution was established, and the total gas-liquid mass transfer coefficient was immediately obtained by measuring the p H value. The corresponding testing platform and process have been established based on the characteristics of the proposed method to ensure fast and accurate measurement. In addition, the chemical absorption method takes into account temperature factors that were not previously considered. The volumetric mass transfer coefficient measured by these two methods is in the same range as those measured by other methods using the same microchannel structure in previous literature. The methods have the advantages of low equipment cost, faster measurement speed, and simpler procedures, which can facilitate its wide application to the evaluation of the mass transfer performance and hence can guide the structure optimization of microchannel reactors.

关键词： Volumetric mass transfer coefficient measurement Gas-liquid two phase Micro reactors Physical absorption Chemical absorption