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Promoting electrocatalytic nitrogen reduction to ammonia via dopant boron on two-dimensional materials

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Rare Metals 2024年第10期43卷 5117-5125页

作者： Ya-Hui cui Wen-Cheng Ouyang Ai-jun Gao Chang-yuan yu Li-Peng Zhang State Key Laboratory of Organic-Inorganic Composites College of Chemical EngineeringBeijing University of Chemical Technology College of Materials Science and Engineering Beijing University of Chemical Technology College of Life Science and Technology Beijing University of Chemical Technology

Electrocatalytic nitrogen reduction reaction(NRR) is a key process for producing energy efficient and environment friendly ammonia. Boron-doped two-dimensional materials are highly promising as NRR ***, the interaction between doped boron and matrix materials on NRR catalytic performance is still unclear,which is limiting the development of catalysts containing boron for NRR. Here, NRR on different boron-doped twodimensional(2D) materials was explored by first principle theory. It is found that adsorption energy of intermediate*NNH(E*NNH) can be used as a descriptor to characterize the catalytic activity for NRR. Boron-adsorbed black phosphorus(B-BP) is demonstrated showing excellent NRR catalytic activity and suppressing hydrogen evolution reaction. It is disclosed that the excellent catalytic performance of boron-doped structures comes from a proper quantitatively electron transfer(0.8e) between nitrogen in*NNH and the active site boron atom. This work not only established a descriptor for NRR catalytic activity on B-doped 2D materials, but also screened out a potential NRR catalyst. More importantly, the intrinsic reason and mechanism of high catalytic activity of boron-doped structures were proposed. This work provides a design principle for exploring high-performance NRR electrocatalysts containing boron.

关键词： Boron-doped two-dimensional materials Density functional theory Descriptor Electrocatalytic nitrogen reduction reaction

Effects of retained dry material on the impact,overflow and landing dynamics

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第9期16卷 3629-3640页

作者： jun Fang Yifei cui Haiming Liu State Key Laboratory of Hydroscience and Engineering Tsinghua UniversityBeijingChina Department of Civil and Environmental Engineering The Hong Kong University of Science and TechnologyHong KongChina

During long-term operation,the performance of obstacles would be changed due to the material accumulating upslope the ***,the effects of retained material on impact,overflow and landing dynamics of granular flow have not yet been *** address this gap,physical flume tests and discrete element simulations are conducted considering a range of normalized deposition height h0/H from 0 to 1,where h0 and H represent the deposition height and obstacle height,*** analytical model is modified to evaluate the flow velocity and flow depth after interacting with the retained materials,which further serve to calculate the peak impact force on the ***,the computed impact forces successfully predict the experimental results when a≥25°.In addition,the results indicate that a higher h0/H leads to a lower dynamic impact force,a greater landing distance L,and a larger landing coefficient Cr,where Cr is the ratio of slope-parallel component of landing velocity to flow velocity just before *** to the existing overflow model,the measured landing distance L is underestimated by up to 30%,and therefore it is insufficient for obstacle design when there is retained ***,the recommended Cr in current design practice is found to be nonconservative for estimating the landing velocity of geophysical *** study provides insightful scientific basis for designing obstacles with deposition.

关键词： Granular flow Obstacle deposition Impact Overflow Landing

Missing microbes in infants and children in the COVID-19 pandemic:a study of 1,126 participants in Beijing,China

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Science China(Life Sciences) 2024年第8期67卷 1739-1750页

作者： Jiejing Wang yuejuan Li yu Mu Kefei Huang Danyi Li Canhui Lan yutao cui jun Wang CAS Key Lab for Pathogenic Microbiology and Immunology Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Beijing Dr.cuiyuTAO Clinic Beijing 100028China R-Institute Co.Ltd. Beijing 100011China

The COVID-19 pandemic has caused many fatalities worldwide and continues to affect the health of the recovered patients in the form of *** this study,we compared the gut microbiome of uninfected infants and children before the pandemic began(BEFORE cohort,n=906)to that of after the pandemic(AFTER cohort,n=220)to examine the potential impact of social distancing and life habit changes on infant/children gut *** on 16S rRNA sequencing,we found a significant change in microbiome composition after the pandemic,with Bacteroides enterotype increasing to 35.45%from 30.46%before the *** quantification indicated that the bacterial loads of seven keystone taxa decreased by 91.69%–19.58%.Quantitative microbiome profiling,used to enhance the resolution in detecting microbiome differences,revealed a greater explained variance of pandemic on microbiome compared to gender,as well as a significant decrease in bacterial loads in 15 of the 20 major *** random forest age-predictor indicated the gut microbiomes were less mature in the after-pandemic cohort than in the before-pandemic cohort in the children group(3–12 years old)and had features of a significantly younger age(average of 1.86 years).Lastly,body weight and height were significantly lower in the after-pandemic cohort than in the before-pandemic cohort in infants(<1 year of age),which was associated with a decrease in bacterial loads in the fecal microbiome.

关键词： gut microbiome COVID-19 pandemic quantitative microbiome profiling children health

Topological Stability and Entropy for Certain Set-valued Maps

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Acta Mathematica Sinica,English Series 2024年第4期40卷 962-984页

作者： yu ZHANG yu jun ZHU School of Mathematical Sciences Xiamen UniversityXiamen 361005P.R.China

In this paper,the dynamics(including shadowing property,expansiveness,topological stability and entropy)of several types of upper semi-continuous set-valued maps are mainly considered from differentiable dynamical systems points of *** is shown that(1)if f is a hyperbolic endomorphism then for eachε>0 there exists a C^(1)-neighborhood U of f such that the induced set-valued map F_(f,U)has theε-shadowing property,and moreover,if f is an expanding endomorphism then there exists a C^(1)-neighborhood U of f such that the induced set-valued map F_(f,U)has the Lipschitz shadowing property;(2)when a set-valued map F is generated by finite expanding endomorphisms,it has the shadowing property,and moreover,if the collection of the generators has no coincidence point then F is expansive and hence is topologically stable;(3)if f is an expanding endomorphism then for eachε>0 there exists a C^(1)-neighborhood U of f such that h(F_(f,U,ε))=h(f);(4)when F is generated by finite expanding endomorphisms with no coincidence point,the entropy formula of F is ***,the dynamics of the set-valued maps based on discontinuous maps on the interval are also considered.

关键词： Set-valued map orbit space hyperbolic endomorphism perturbation shadowing expansiveness topological stability entropy

Factors and Their Impact on Treatment Effect of Acupuncture in Different Outcomes:A Meta-Regression of Acupuncture Randomized Controlled Trials

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Chinese Journal of Integrative Medicine 2024年第3期30卷 260-266页

作者： XIU Wen-cui GANG Wei-juan ZHOU Qi SHI Lan-jun HU Xiang-yu MING Tian-yu LUO Zhen ZHANG yu-qing JING Xiang-hong Institute of Acupuncture and Moxibustion China Academy of Chinese Medical SciencesBeijing100700China China Center for Evidence-Based Traditional Chinese Medicine China Academy of Chinese Medical SciencesBeijing100700China Department of Health Research Methods Evidenceand ImpactMcMaster UniversityHamiltonOntarioL8S 4L8Canada Center for Evidence-Based Integrative Medicine-Clarity Collaboration Guang’anmen HospitalChina Academy of Chinese Medical SciencesBeijing100053China

Background:The effects of acupuncture have varied in different randomized controlled trials(RCTs),and there are many factors that influence treatment effect of acupuncture in different outcomes,with conflicting ***:To identify factors and their impact on the treatment effect of acupuncture in different ***:Acupuncture RCTs were searched from 7 databases including Medline(Pub Med),Embase,Cochrane Central Register of Controlled Trials,China National Knowledge Infrastructure,Wanfang Database,VIP Database,and China Biology Medicine disc between January 1st,2015 and December 31st,*** studies must compare acupuncture to no acupuncture,sham acupuncture,or waiting lists,and report at least 1patient-important outcome.A multi-level meta-regression was conducted using a 3-level robust mixed model and univariate analyses were performed for all independent variables,even those excluded from the multivariable model due to *** used thresholds of 0.2 and 0.4 for the difference of standardized mean differences(SMDs),categorising them as small(0.4) ***:The pain construct analysis involved 211 effect estimates from 153 studies and 14 independent ***-frequency acupuncture treatment sessions produced larger effects compared to low-frequency sessions [large magnitude,the difference of adjusted SMDs 0.46,95% confidence interval(CI) 0.07 to 0.84;P=0.02].The non-pain symptoms construct analysis comprised 323 effect estimates from 231 studies and 15 independent *** acupuncture showed moderately larger effects when compared to non-penetrating acupuncture(0.30,95% CI 0.06 to 0.53;P=0.01).The function construct analysis included 495 effect estimates from 274 studies and 14 independent *** acupuncture and the flexible acupuncture regimen showed moderately larger effects,compared to non-penetrating acupuncture and fixed regimen,respectively(0.40,95% CI 0

关键词： acupuncture randomized controlled trial patient-important outcome meta-regression

Studying the stress-suction coupling in soils using an oedometer equipped with a high capacity tensiometer

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Frontiers of Structural and Civil Engineering 2011年第2期5卷 160-170页

作者： Trung Tinh LE yu-jun cui Juan Jorge MUÑOZ Pierre DELAGE Anh Minh TANG Xiang-Ling LI Ecole des ponts ParisTech Navier/CERMES6-8av.B.PascalCitéDescartesChamps-sur-Marne77455 Marne-la-Vallée cedex 2France The China Three Gorges University Yichang 443002China EURIDICE Group c/o SCK./CENBoeretang 2002400 MolBelgium

In the context of research into deep nuclear waste disposal,various works have concerned the hydromechanical behavior of Boom clay,a stiff plastic clay extracted in the SCK-CEN Underground Research Laboratory near the Mol City(Belgium),at a depth of 223 *** to some amount of smectite minerals in the clay fraction,Boom clay exhibits swelling properties when hydrated under low *** investigate some aspects of the hydromechanical behavior of Boom clay,oedometer compression tests were carried out on samples of Boom clay close to saturation and submitted to an initial *** oedometer compression,the changes in suction with increased vertical stress are monitored by means of a high capacity tensiometer installed at the bottom of the *** aspects related to hydromechanical couplings are examined through the investigation of the changes in suction during oedometer compression,a somewhat delicate and poorly documented experimental approach.A comparison is also made with a completely different soil sample under suction,i.e.a statically compacted unsaturated low plasticity *** technical difficulties typical of this new experimental approach are first described in detail so as to optimize the interpretation of the data *** experiment allows the determination of the point at which suction is changed to positive pressure during *** this point,the ratio between the vertical stress and the change in suction are *** this point,the data show that positive pore pressures are dissipated in a common *** suction/stress behavior during unloading is also described and ***,an interpretation in terms of microstructure effects is provided for both *** experimental approach initiated here seems to provide interesting further application to better understand hydromechanical couplings in natural soils in relation with suction increase during stress release.

关键词： Oedometer tensiometer swelling physicochemical and mechanical effects stress/suction coupling soil plasticity

Spatial distribution of shallow landslides caused by Typhoon Lekima in 2019 in Zhejiang Province, China

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Journal of Mountain Science 2024年第5期21卷 1564-1580页

作者： cui yulong YANG Liu XU Chong ZHENG jun School of Civil Engineering and Architecture Anhui University of Science and TechnologyHuainan 232001China National Institute of Natural Hazards Ministry of Emergency Management of ChinaBeijing 100085China Department of Civil Engineering Zhejiang UniversityHangzhou 310058China

In recent years, the coastal region of Southeast China has witnessed a significant increase in the frequency and intensity of extreme rainfall events associated with landfalling typhoons. The hilly and mountainous terrain of this area, combined with rapid rainfall accumulation, has led to a surge in flash floods and severe geological hazards. On August 10, 2019, Typhoon Lekima made landfall in Zhejiang Province, China, and its torrential rainfall triggered extensive landslides, resulting in substantial damage and economic losses. Utilizing high-resolution satellite images, we compiled a landslide inventory of the affected area, which comprises a total of 2,774 rainfallinduced landslides over an area of 2965 km2. The majority of these landslides were small to mediumsized and exhibited elongated, clustered patterns. Some landslides displayed characteristics of high-level initiation, obstructing or partially blocking rivers, leading to the formation of debris dams. We used the inventory to analyze the distribution pattern of the landslides and their relationship with topographical, geological, and hydrological factors. The results showed that landslide abundance was closely related to elevation, slope angle, faults, and road density. The landslides were predominantly located in hilly and low mountainous areas, with elevations ranging from 150 to 300 m, slopes of 20 to 30 degrees, and a NE-SE aspect. Notably, we observed the highest Landslide Number Density(LND) and Landslide Area Percentage(LAP) in the rhyolite region. Landslides were concentrated within approximately 4 km on either side of fault zones, with their size and frequency negatively correlated with distances to faults, roads, and river systems. Furthermore, under the influence of typhoons, regions with denser vegetation cover exhibited higher landslide density, reaching maximum values in shrubland areas. In areas experiencing significantly increased concentrated rainfall, landslide density also showed a corr

关键词： Typhoon rainfall Landslide characteristics Spatial distribution Southeast coastal region

Influences of the tank liquid lateral sloshing and mass time-varying on high clearance self-propelled sprayer ride comfort

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International Journal of Agricultural and Biological Engineering 2024年第1期17卷 12-22页

作者： Liquan Lu junchang Zhang cui cui jun Chen yu Chen Hongling Jing Shuo Zhang Sugirbay Adilet Chenwei Hu Jiayu Cao College of Mechanical and Electronic Engineering Northwest A&F UniversityYangling 712100ShaanxiChina Weifang Engineering Vocational College Weifang 261000ShandongChina Technical Faculty S.Seifullin Kazakh Agro Technical UniversityAstana 101400Kazakhstan

To explore the influence of the lateral sloshing and the time-varying mass of the liquid in the tank on the ride comfort of the high-clearance sprayer,a spring-mass-damping equivalent mechanics that can describe the lateral sloshing of the liquid under different filling ratios was constructed based on the equivalent *** Fluent was used to simulate the moment acting on the wall of the tank by the lateral sloshing of the liquid,and then the parameters of the equivalent mechanical model are obtained by fitting and *** analysis of Fluent simulation and bench test on lateral sloshing of tank liquid under different filling *** results show that the lateral sloshing trend of the tank liquid level obtained from the Fluent simulation and the bench test was consistent,which proved the accuracy of the Fluent fluid simulation process and the correctness of the required equivalent mechanical model *** a liquid sloshing equivalent model,a four-degree-of-freedom vertical dynamic model of the sprayer half-car was ***,the performance of the sprayer was systematically analyzed and compared under the excitation of a bump road and a random E-level *** investigation took into account varying liquid filling ratios of 10%,50%,and 90%.The focus lay on evaluating the vertical acceleration of the sprayer body,dynamic deflection of the suspension,and dynamic load on the tires in response to these road *** analysis is conducted independently of the liquid sloshing *** results show that the lateral sloshing of the liquid medicine significantly reduces the ride smoothness of the machine,and makes the vibration response of the machine produce a certain hysteresis *** the reduction of the quality of the liquid medicine in the spray tank,the vibration amplitude of the sprayer body gradually decreases,the hysteresis effect is also gradually *** results presented in this study offer a

关键词： high clearance self-propelled sprayer liquid lateral sloshing ride comfort system dynamics simulation

Clinical pathological characteristics of“crawling-type”gastric adenocarcinoma cancer:A case report

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World Journal of Gastrointestinal Oncology 2024年第4期16卷 1660-1667页

作者： Yong-Wei Xu Yan Song jun Tian Ba-cui Zhang yu-Sheng Yang Jing Wang Department of Gastroenterology Songjiang HospitalSchool of MedicineShanghai Jiaotong UniversityShanghai 201600China Department of Pathology Songjiang HospitalSchool of MedicineShanghai Jiaotong UniversityShanghai 201600China

BACKGROUND Gastric cancer(GC)is a significant health problem worldwide,and early detection and accurate diagnosis are crucial for improving patient ***-type gastric adenocarcinoma is a rare subtype of GC that has unique histopathological and clinical characteristics,and its diagnosis and management can be *** pathological type of GC is also *** SUMMARY Here,we report the case of a patient who underwent ordinary endoscopy,na-rrow-band imaging,and endoscopic ultrasonography intending to determine the extent of tumor invasion and upper abdominal enhanced computed tomography and whether there was tumor ***,endoscopic submucosal dissection was *** pathological and immunohistochemical examination,the pathological diagnosis was crawling-type gastric *** is a very rare and special pathological type of *** case highlights the importance of using advanced endoscopic techniques and pathological examination in diagnosing and managing gastric crawling-type ***,the findings underscore the need for continued research and clinical experience in this rare subtype of GC to improve patient *** The“crawling-type”GC is a rare and specific tumor *** is difficult to identify and diagnose gliomas via *** tumor is ill-defined,with a flat appearance and indistinct borders due to the lack of contrast against the background *** revealed that the tumor cells were hand-like,so the patient has diagnosed with“crawling-type”gastric adenocarcinoma.

关键词： Clinicopathological Crawling-type gastric Pathology Gastric cancer Gastric adenocarcinoma cancer Case report