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Hydrochemical insights on the signatures and genesis of water resources in a high-altitude city on the Qinghai-Xizang Plateau, South-west China

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Frontiers of Environmental Science & Engineering 2024年第7期18卷 123-140页

作者： Jiutan Liu Kexin Lou Zongjun Gao Menghan tan College of Earth Science and Engineering Shandong University of Science and TechnologyQingdao 266590China

Water resources have crucial implications for the steady development of the urban social *** study investigated the hydrochemical signatures and genesis of water resources in the urban area of Lhasa City(UALC).To this end,several analyses,such as ion ratio analysis and correlation analysis,were performed by comprehensively applying mathematical statistics and integrated hydrochemical *** results show relatively low concentrations of major ions in the groundwater and surface water(GSW)of the *** primary anions and cations are HCO3-and Ca2+,reflecting the HCOg-Ca water ***,groundwater exhibits higher concentrations of key chemical components compared to surface *** are weakly alkaline,with pH values of 7.78 and 7.61,respectively,and they have low salinity with average concentrations of total dissolved solids being 190.74 and 112.17 mg/L,*** inputs have minimal influence on the hydrochemical features of GSw,whereas rock weathering is the dominant controlling ***,cation *** a significant *** influencing their hydrochemical *** to the isotope analysis(H and 180),the primary source of recharge for GSW is atmospheric precipitation,with some input from melted ice and ***,GSW samples from the UALC show relatively similar 2H and 18O isotopic compositions,indicating the existence of a discernible hydraulic connection linking the two water *** research findings can serve as a valuable scientific reference and foundation for the sustainable development,effective utilization,and proper safeguarding of regional water resources in high-altitude areas.

关键词： Groundwater and surface water Hydrochemical features Genesis mechanism Water quality Urban area of Lhasa City

Analysis on carbon emission reduction intensity of fuel cell vehicles from a life-cycle perspective

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Frontiers in Energy 2024年第1期18卷 16-27页

作者： Ziyuan TENG Chao tan Peiyuan LIU Minfang HAN Fuel Cell and Energy Storage Center Department of Energy and Power EngineeringState Key Laboratory of Control and Simulation of Power Systems and Generation EquipmentTsinghua UniversityBeijing 100084China

The hydrogen fuel cell vehicle is rapidly developing in China for carbon reduction and *** paper evaluated the life-cycle cost and carbon emission of hydrogen energy via lots of field surveys,including hydrogen production and packing in chlor-alkali plants,transport by tube trailers,storage and refueling in hydrogen refueling stations(HRSs),and application for use in two different *** also conducted a comparative study for battery electric vehicles(BEVs)and internal combustion engine vehicles(ICEVs).The result indicates that hydrogen fuel cell vehicle(FCV)has the best environmental performance but the highest energy ***,a sufficient hydrogen supply can significantly reduce the carbon intensity and FCV energy cost of the current *** carbon emission for FCV application has the potential to decrease by 73.1%in City A and 43.8%in City *** only takes 11.0%–20.1%of the BEV emission and 8.2%–9.8%of the ICEV *** cost of FCV driving can be reduced by 39.1%in City *** improvement can be obtained with an economical and“greener”hydrogen production pathway.

关键词： hydrogen energy life-cycle assessment(LCA) fuel cell vehicle carbon emission energy cost

Design of acceleration control schedule for adaptive cycle engine based on direct simulation model

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Chinese Journal of Aeronautics 2024年第6期37卷 307-318页

作者： Keran SONG Linyuan JIA Yuchun CHEN Tian tan School of Power and Energy Northwestern Polytechnical UniversityXi’an 710072China

To design the optimum acceleration control schedule for the Adaptive Cycle Engine(ACE)in the full flight envelope,this paper establishes a direct simulation model of the ACE transient *** this model,geometric parameters are used to replace the component state *** corresponding relationship between geometric parameters and component state parameters is determined by sensitivity *** geometric variables are controlled when the geometric adjustment speed exceeds the limit,and at the same time the corresponding component state parameters are *** gradient optimization algorism is used to optimize the ground acceleration process of ACE,and the control schedule in terms of operating point of compression components and corrected acceleration rate is used as the full-envelope acceleration control schedule based on the similarity *** acceleration control schedules of the triple-bypass mode and the double-bypass mode are designed in this *** acceleration processes under various flight conditions are simulated using the acceleration control *** with the acceleration process with the linear geometric adjustment schedule,the acceleration performance of ACE is improved by the acceleration control schedule,with the impulse of the acceleration process of the triple-bypass mode being increased by 8.7%-12.3% and the impulse of the double-bypass mode acceleration process being increased by 11.8%-14.1%.

关键词： Adaptive Cycle Engine(ACE) Direct simulation method Acceleration Control schedule Full flight envelope

Organic stabilization in earthen plaster:Eco-compatible architecture and ancient techniques in Tata Somba homes

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Frontiers of Architectural Research 2024年第3期13卷 625-638页

作者： D.ben Ghida Department of Architecture University of Naples FedericoⅡNaplesItaly

The study of organic stabilization is crucial for understanding its impact on the durability and effectiveness of earthen *** natural admixtures’effects on plaster properties provides insights that aid in optimizing plaster composition and application for desired *** addition of biopolymers,known to enhance plaster performance,necessitates further investigation to understand their role in earthen plaster *** study focuses on Tata Somba homes in benin and Togo,recognized as UNESCO World Heritage *** unique architectural examples embody“architecture without architects”,relying solely on local traditional *** objective is to explore and revive Tata Somba’s ancient eco-technology for earth plaster *** shows that biopolymers’combined stabilization and application techniques can improve earthen plaster *** promising bio-stabilizers were identified,suggesting their potential as sustainable,effective options for CO_(2) mitigation in *** findings not only deepen our understanding of earthen architecture but also underscore the potential of merging traditional,eco-friendly building methods with modern scientific insights to create sustainable solutions for cultural heritage preservation and contemporary built environments.

关键词： Vernacular architecture Cultural heritage preservation Sustainable architecture Biopolymer Earth architecture Earth stabilization

Mechanical behavior and damage constitutive model of sandstone under hydro-mechanical (H-M) coupling

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International Journal of Mining Science and Technology 2024年第6期34卷 837-853页

作者： Tao tan Chunyang Zhang Yanlin Zhao Xiaoshuang Li School of Resources and Environmental Engineering Wuhan University of TechnologyWuhan 430070China State Key Laboratory of Safety and Health in Metal Mines Maanshan 243000China Sinosteel Maanshan General Institute of Mining Research Co. Ltd.Maanshan 243000China School of Resource&Environment and Safety Engineering Hunan University of Science and TechnologyXiangtan 411201China School of Urban Construction Changzhou UniversityChangzhouJiangsu 213164China

Underground engineering often passes through water-rich fractured rock masses, which are prone to fracture and instability under the long-term coupling of in-situ stress field and pore water(P-W) pressure, ultimately threatening the stability of underground structures. In order to explore the mechanical properties of rocks under H-M coupling, the corresponding damage constitutive(D-C) model has become the focus of attention. Considering the inadequacy of the current research on rock strength parameters,energy evolution characteristics and D-C model under H-M coupling, the mechanical properties of typical sandstone samples are discussed based on laboratory tests. The results show that the variation of characteristic stresses of sandstone under H-M coupling conforms to the normalized attenuation equation and Mohr-Coulomb(M-C) criterion. The P-W pressure mechanism of sandstone exhibits a dynamic change from softening effect to H-M fracturing effect. The closure stress is mainly provided by cohesive strength, while the initiation stress, damage stress, and peak stress are jointly dominated by cohesive strength and friction strength. In addition, residual stress is attributed to the friction strength formed by the bite of the fracture surface. Subsequently, the energy evolution characteristics of sandstone under H-M coupling were studied, and it was found that P-W pressure weakened the energy storage capacity and energy dissipation capacity of sandstone, and H-M fracturing was an important factor in reducing its energy storage efficiency. Finally, combined with energy dissipation theory and statistical damage theory, two types of D-C models considering P-W pressure are proposed accordingly, and the model parameters can be determined by four methods. The application results indicate that the proposed and modified D-C models have high reliability, and can characterize the mechanical behavior of sandstone under H-M coupling, overcome the inconvenience of existing D-C models

关键词： H-M coupling Water-saturated sandstone Mechanical mechanism Energy evolution D-C model

Interaction of yttrium barrier and calcium-rich phase on production and properties of WC precursor powders and alloys

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Journal of Rare Earths 2024年第1期42卷 228-236,I0008页

作者： Wen He Dunqiang tan Zhiqiang Yi Zhiqiang Liu School of Materials Science and Engineering Nanchang UniversityNanchang330031China Instrumental Analysis Center of Nanchang Hangkong University Nanchang330063China

In order to reduce or eliminate the adverse effects of calcium impurity,the interaction of Ca and rare earth Y co-doping on the preparation of WC-Co cemented carbides was investigated.X-ray diffraction,scanning electron microscopy and transmission electron microscopy were employed to analyze the phase compositions,particle sizes and morphologies of them,*** results show that the second type of"yttrium barrier effect"is observed and the adverse influence of Ca-rich phase on tungsten powder can be eliminated by *** flexural strength and fracture toughness of YG6-0.01%Ca+0.09%Y alloy are 2199.5 MPa and 11.49 MPa·m^(1/2),showing improvement of 6.5% and 2.7% compared to YG6 alloy,*** evolutions of Ca-rich phase and Y-rich phase at the every alloy preparation stage of WO_(3),W,WC and cemented carbides are ***,the strengthening mechanism of WC-Co cemented carbide with co-addition of Ca and Y is proposed.

关键词： Yttrium barrier effect Ca-rich phase WC-Co cemented Carbide Microstructures Mechanisms Rare earths

Recursive Filtering for Stochastic Systems With Filter-and-Forward Successive Relays

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IEEE/CAA Journal of Automatica Sinica 2024年第5期11卷 1202-1212页

作者： Hailong tan Bo Shen Qi Li Hongjian Liu School of Mathematics-Physics and Finance Anhui Polytechnic UniversityWuhu 241000China Anhui Future Technology Research Institute Anhui Polytechnic UniversityWuhu 241000China College of Information Science and Technology Donghua UniversityShanghai 201620China Engineering Research Center of Digitalized Textile and Fashion Technology Ministry of EducationShanghai 201620China School of Information Science and Engineering Hangzhou Normal UniversityHangzhou 311121China

In this paper,the recursive filtering problem is considered for stochastic systems over filter-and-forward successive relay(FFSR)*** FFSR is located between the sensor and the remote filter to forward the *** the successive relay,two cooperative relay nodes are adopted to forward the signals alternatively,thereby existing switching characteristics and inter-relay interferences(IRI).Since the filter-and-forward scheme is employed,the signal received by the relay is retransmitted after it passes through a linear *** objective of the paper is to concurrently design optimal recursive filters for FFSR and stochastic systems against switching characteristics and IRI of ***,a uniform measurement model is proposed by analyzing the transmission mechanism of ***,novel filter structures with switching parameters are constructed for both FFSR and stochastic *** the help of the inductive method,filtering error covariances are presented in the form of coupled difference ***,the desired filter gain matrices are further obtained by minimizing the trace of filtering error ***,the stability performance of the filtering algorithm is analyzed where the uniform bound is guaranteed on the filtering error ***,the effectiveness of the proposed filtering method over FFSR is verified by a three-order resistance-inductance-capacitance circuit system.

关键词： filtering successive stochastic

Clinical characteristics and genetic mutations of 10 Chinese children with cystic fibrosis or cystic frbrosis transmembrane conductance regulator-related disorders

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中华医学杂志(英文版) 2024年第14期137卷 1753-1755页

作者： tan Shanshan Cao Ling Department of Pulmonology The Children’s Hospital Affiliated to the Capital Institute of Pediatrics Beijing China

To the Editor: Cystic fibrosis (CF) is an autosomal recessive disorder caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. To date, over 2000 CFTR mutations have been identified. CF mostly occurs in the Caucasian population, and its incidence is approximately 1/25,000 to 1/1800. However, the number of CF cases in China is small. To discover the gene mutations and clinical characteristics of Chinese children with CF, as well as their correlation, the clinical data of 10 children with CF or CFTR-related disorders (CFTR-RD) were retrospectively analyzed in this study.

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Copper-catalyzed asymmetric dearomatizing amination of 2-naphthols:Csp^(2)–N coupling via 1,3-reductive elimination

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Science China Chemistry 2024年第8期67卷 2694-2700页

作者： Aying Yihuo Maoping Pu Zheng tan Jibang Liao Jiuqi tan Qi-Lin Zhou Xiaohua Liu Xiaoming Feng Key Laboratory of Green Chemistry&Technology Ministry of EducationCollege of ChemistrySichuan UniversityChengdu 610064China Key Laboratory and Institute of Elemento-Organic Chemistry College of Chemistry Frontiers Science Centerfor New Organic MatterNankai UniversityTianjin300071China

An efficient catalytic asymmetric dearomatizing amination of 2-naphthols and phenols catalyzed by N,N′-dioxide-copper(I)complex as a chiral catalyst was presented.A variety of optically activeβ-naphthalenone compounds with a nitrogen-containing quaternary carbon stereocenter were obtained with high yield and enantioselectivity under mild reaction *** studies indicated that this Csp^(2)–N dearomatizing coupling proceeds via 1,3-reductive elimination of phenolate-Cu~Ⅲ-amino intermediate in five-membered ring transition *** origin of enantioselectivity has also been elucidated based on density functional theory calculations.

关键词： asymmetric catalysis amination dearomatization copper catalysis coupling reaction