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Science China Chemistry 2024年第3期67卷 953-962页

作者： Yuan-Qing gu Hong-Xin Long Dan-Dan Zhang mei-Feng Ruan guo-Kai Liu School of Pharmacy Shenzhen University Medical SchoolShenzhen UniversityShenzhen 518055China

Development of practical and versatile electrophilic difluoromethylating reagent is still a grand challenge so far due to its inherent instability or low ***,we report the design and synthesis of difluoromethyl phenoxathiinium tetrafluoroborate(PT-CF_(2)H^(+)BF_(4)^(-)) as a novel difluoromethylating reagent,which proves to be a bench-stable,general,powerful and versatile reagent with divergent·CF_(2)H,CF_(2)H^(+),and:CF_(2) *** use of this reagent,we demonstrated a vast array of difluoromethyl radical transfer reactions via diverse pathways involving photocatalyst-free visible-light induction,visible-light photoredox catalysis and visible-light mediation single electron transfer of EDA ***,the green and highly effective CF_(2)H^(+) and:CF_(2) transfer reactions were also readily accomplished.

关键词： difluoromethyl phenoxathiinium salt versatile difluoromethylating reagent difluoromethyl radical difluoromthyl cation difluorocarbene

Nonexistence of quantum black and white hole horizons in an improved dynamic approach

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Science China(Physics,Mechanics & Astronomy) 2024年第8期67卷 56-73页

作者： Wen-Cong Gan Xiao-mei Kuang zhen-Hao Yang Yungui Gong Anzhong Wang Bin Wang College of Physics and Communication Electronics Jiangxi Normal UniversityNanchang 330022China GCAP-CASPER Physics DepartmentBaylor UniversityWaco 76798-7316USA Institute for Theoretical Physics&Cosmology Zhejiang University of TechnologyHangzhou 310023China United Center for Gravitational Wave Physics(UCGWP) Zhejiang University of TechnologyHangzhou 310023China Center for Gravitation and Cosmology College of Physical Science and TechnologyYangzhou UniversityYangzhou 225009China Department of Physics School of Physical Science and TechnologyNingbo UniversityNingbo 315211China School of Aeronautics and Astronautics Shanghai Jiao Tong UniversityShanghai 200240China

In this paper,we study the quantum geometric effects near the locations where classical black hole horizons used to appear in Einstein's classical theory,within the framework of an improved dynamic approach,in which the internal region of a black hole is modeled by the Kantowski-Sachs(KS)spacetime and the two polymerization parameters are functions of the phase space *** detailed analysis shows that the effects are so strong that black and white hole horizons of the effective quantum theory do not exist at all and instead are replaced by transition surfaces,across which the metric coefficients and their inverses are smooth and remain finite,as are the corresponding curvatures,including the Kretschmann *** surfaces always separate trapped regions from anti-trapped *** number of such surfaces is infinite,so the corresponding KS spacetimes become geodesically complete,and no black and white hole-like structures exist in this scheme.

关键词： canonical quantization loop quantum gravity quantum aspects of black holes

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Dynamic Response of A Group of Cylindrical Storage Tanks with Baffles Considering the Effect of Soil Foundation

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China Ocean Engineering 2024年第1期38卷 129-143页

作者： SUN Ying WANG Jia-dong HUO Rui-li ZHOU Ding gu zhen-yuan QIAN Wang-ping School of Transportation and Civil Engineering Nantong UniversityNantong 226019China Faculty of Civil Engineering and Mechanics Jiangsu UniversityZhenjiang 212013China College of Civil Engineering Nanjing Tech UniversityNanjing 211816China

The sloshing in a group of rigid cylindrical tanks with baffles and on soil foundation under horizontal excitation is studied *** solutions for the velocity potential are derived out by the liquid subdomain *** models with mass-spring oscillators are established to replace continuous *** with the least square technique,Chebyshev polynomials are employed to fit horizontal,rocking and horizontal-rocking coupling impedances of soil,respectively.A lumped parameter model for impedance is presented to describe the effects of soil on tank structures.A mechanical model for the soil-foundation-tank-liquid-baffle system with small amount of calculation and high accuracy is proposed using the substructure *** analytical solutions are in comparison with data from reported literature and numerical codes to validate the effectiveness and correctness of the *** dynamic properties and seismic responses of the soil-tank system are given for the baffle number,size and location as well as soil parameter.

关键词： cylindrical tanks multiple annular baffles equivalent analytical model soil−structure interaction subdomain method dynamic response

Aseismic performances of constrained damping lining structures made of rubber-sand-concrete

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第5期16卷 1522-1537页

作者： Xiancheng mei Qian Sheng Jian Chen zhen Cui Jianhe Li Chuanqi Li Daniel Dias State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China University of Chinese Academy of Sciences Beijing100049China Key Laboratory of Water Grid Project and Regulation of Ministry of Water Resources Changjiang Institute of SurveyPlanningDesign and ResearchWuhan430010China Laboratory 3SR CNRS UMR 5521Grenoble Alpes UniversityGrenoble38000France School of Automotive and Transportation Engineering Hefei University of TechnologyHefei23009China

Flexible damping technology considering aseismic materials and aseismic structures seems be a good solution for engineering *** this study,a constrained damping structure for underground tunnel lining,using a rubber-sand-concrete(RSC)as the aseismic material,is *** aseismic performances of constrained damping structure were investigated by a series of hammer impact *** damping layer thickness and shape effects on the aseismic performance such as effective duration and acceleration amplitude of time-domain analysis,composite loss factor and damping ratio of the transfer function analysis,and total vibration level of octave spectrum analysis were *** hammer impact tests revealed that the relationship between the aseismic performance and damping layer thickness was not linear,and that the hollow damping layer had a better aseismic performance than the flat damping layer *** aseismic performances of constrained damping structure under different seismicity magnitudes and geological conditions were *** effects of the peak ground acceleration(PGA)and tunnel overburden depth on the aseismic performances such as the maximum principal stress and equivalent plastic strain(PEEQ)were *** numerical results show the constrained damping structure proposed in this paper has a good aseismic performance,with PGA in the range(0.2-1.2)g and tunnel overburden depth in the range of 0-300 m.

关键词： Constrained damping structure Aseismic performance Hammer impact tests Damping layer Peak ground acceleration Overburden depth

Differential bonding behaviors of sodium/potassium-ion storage in sawdust waste carbon derivatives

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Chinese Chemical Letters 2024年第4期35卷 496-501页

作者： Jun-Ming Cao Kai-Yang Zhang Jia-Lin Yang zhen-Yi gu Xing-Long Wu MOE Key Laboratory for UV Light-Emitting Materials and Technology Northeast Normal UniversityChangchun 130024China Department of Chemistry Northeast Normal UniversityChangchun 130024China

Sodium-ion batteries(SIBs) and potassium-ion batteries(PIBs) are the most promising alternatives to lithium-ion batteries, and thus have drawn intensive research attention. Porous carbon materials from different precursors have been widely used as anode materials owing to their compatible storage effectiveness of both larger radii sodium and potassium ions. However, the differential bonding behaviors of Na and K ions with porous carbon-based anode are the significant one worth investigating, which could provide a clean picture of alkali ions storage mechanism. Therefore, in this work, we prepare a porous carbon network derived from sawdust(SDC) wastes, to further analyze the differences on sodium and potassium ions storage behaviors in terms of bond-forming process. It is found that, as-prepared SDC anodes could deliver stable sodium and potassium storage capacities, however, there are notable distinctions in terms of electrochemical behaviors and diffusion processes. By virtue of ex-situ XRD and Raman spectroscopy, the phase transition reaction of potassium ions could be well-observed, and the results shows that the multiple intercalated compounds was formed in SDC network during ions insertion, further resulting in slower diffusion kinetics and larger resistance compared to non-bonded process of sodium ions storage. This study provides more insights into the differences between sodium and potassium ions storage, as well as the energy storage mechanism of porous carbon as anodes for secondary batteries.

关键词： Porous carbon Sodium-ion storage Potassium-ion storage Bonding behaviors Batteries

Liquid-phase epitaxial layer by layer brushing fabrication of metalorganic frameworks films

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Nano Research 2024年第6期17卷 5698-5704页

作者： Li-mei Chang Rui Zhai Zhi-Zhou Ma Jian-Dong Huang Zhi-Gang gu Jian Zhang College of Chemistry Fuzhou UniversityFuzhou 350108China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China University of Chinese Academy of Sciences Beijing 100049China

Development of metal-organic framework(MOF)films is of great importance to expand their ***,we report a facile and universal method of liquid-phase epitaxial(LPE)layer by layer(LBL)brushing approach for fabricating MOF films on various substrates in a high-throughput *** MOF films preparation method offers a great prospective to cost-effectively construct films with short preparation time and little reagent ***,this LBL brushing approach has been implemented successfully to assemble various MOF films,including HKUST-1,zeolitic imidazolate framework-8(ZIF-8),Cu(bdc),and Cu_(2)(L)_(2)P(L=bdc,ndc,and cam;P=dabco and bipy).Afterwards,the classic MOF HKUST-1 and ZIF-8 films were grown on sensor chip electrode and porous fiber support for good volatile organic compounds(VOCs)selective sensing and water purification *** study demonstrates that this LBL brushing preparation method can be employed to synthesize various MOF films with a variety of characteristics to realize their sensing and separation applications.

关键词： metal-organic framework porous materials layer by layer fabrication film

Aerodynamic Features of High-Speed Maglev Trains with Different Marshaling Lengths Running on a Viaduct under Crosswinds

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Computer Modeling in Engineering & Sciences 2024年第7期140卷 975-996页

作者： Zun-Di Huang zhen-Bin Zhou Ning Chang zheng-Wei Chen Su-mei Wang School of Rail Transportation Wuyi UniversityJiangmen529020China National Rail Transit Electrification and Automation Engineering Technology Research Center(Hong Kong Branch) The Hong Kong Polytechnic UniversityHong Kong999077China Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHong Kong999077China

The safety and stability of high-speed maglev trains traveling on viaducts in crosswinds critically depend on their aerodynamic ***,this paper uses an improved delayed detached eddy simulation(IDDES)method to investigate the aerodynamic features of high-speed maglev trains with different marshaling lengths under *** effects of marshaling lengths(varying from 3-car to 8-car groups)on the train’s aerodynamic performance,surface pressure,and the flow field surrounding the train were investigated using the three-dimensional unsteady compressible Navier-Stokes(N-S)*** results showed that the marshaling lengths had minimal influence on the aerodynamic performance of the head and middle ***,the marshaling lengths are negatively correlated with the time-average side force coefficient(CS)and time-average lift force coefficient(Cl)of the tail *** to the tail car of the 3-car groups,the CS and Cl fell by 27.77%and 18.29%,respectively,for the tail car of the 8-car *** is essential to pay more attention to the operational safety of the head car,as it exhibits the highest time average ***,the mean pressure difference between the two sides of the tail car body increased with the marshaling lengths,and the side force direction on the tail car was opposite to that of the head and middle ***,the turbulent kinetic energy of the wake structure on the windward side quickly decreased as marshaling lengths increased.

关键词： High-speed maglev train marshaling lengths crosswinds aerodynamic features

One-year observation of the mixing states of oxygenated organics-containing single particles in guangzhou,China

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Frontiers of Environmental Science & Engineering 2024年第5期18卷 155-169页

作者： Liyuan Mao Suxia Yang Xiaoya Cheng Sulin Liu Duanying Chen zhen Zhou mei Li Chenglei Pei Chunlei Cheng Institute of Mass Spectrometry and Atmospheric Environment Guangdong Provincial Engineering Research Center for the On-line Source Apportionment System of Air PollutionJinan UniversityGuangzhou510632China guangdong-Hongkong-Macao Joint Laboratory of Collaborative Innovation for Environmental Quality Guangzhou510632China guangzhou Research Institute of Environment Protection Co. Ltd.Guangzhou510620China guangzhou Ecological and Environmental Monitoring Center of guangdong Province Guangzhou510030China State Key Laboratory of Marine Resource Utilization in South China Sea Hainan UniversityHaikou570228China State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy SciencesXi’an710061China

Oxygenated organic molecules(OOMs)play an important role in the formation of secondary organic aerosols(SOAs),but the mixing states of OOMs are still *** study investigates the mixing states of OOM-containing single particles from the measurements taken using a single particle aerosol mass spectrometer in guangzhou,China in ***,the particle counts of OOM particles and the mass concentration of secondary organic carbon(SOC)exhibited similar temporal trends throughout the entire *** OOM particles were consistently enriched in secondary ions,including ^(16)O^(−),^(26)CN^(−),^(46)NO_(2)^(−),^(62)NO_(3)^(−),and ^(97)HSO_(4)^(−).In contrast,the number fractions and diurnal patterns of OOM particles among the total detected particles showed similar distributions in August and October;however,the SOC ratios in fine particulate matter were quite different,suggesting that there were different mixing states of single-particle oxygenated *** addition,further classification results indicated that the OOM particles were more aged in October than August,even though the SOC ratios were higher in ***,the distribution of hydrocarbon fragments exhibited a notable decrease from January to October,emphasizing the more aged state of the organics in *** addition,the sharp increase in elemental carbon(EC)-OOM particles in the afternoon in October suggests the potential role of EC in the aging process of ***,in contrast to the bulk analysis of SOC mass concentration,the mixing states of the OOM particles provide insights into the formation process of SOAs in field studies.

关键词： Oxygenated organics Single particles Mixing state Secondary formation Photochemistry

Ability of Helicobacter pylori to internalize into Candida

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World Journal of Gastroenterology 2024年第16期30卷 2281-2284页

作者： zheng-Hong Chen Jian-Chao Sun Ting-Xiu Yang gu-zhen Cui Key Laboratory of Microbiology and Parasitology of Education Department of guizhou Guizhou Medical UniversityGuiyang 561113Guizhou ProvinceChina Key Laboratory of Endemic and Ethnic Diseases of Ministry of Education Guizhou Medical UniversityGuiyang 561113Guizhou ProvinceChina Joint Laboratory of Helicobacter Pylori and Intestinal Microecology Affiliated Hospital of Guizhou Medical UniversityGuiyang 550009Guizhou ProvinceChina Department of Quality Control Guizhou Provincial Center for Clinical LaboratoryGuiyang 550002Guizhou ProvinceChina Department of Hospital Infection and Management Guizhou Provincial People’s HospitalGuiyang 550002Guizhou ProvinceChina

The following are our views regarding the“letter to the editor”(Helicobacter is preserved in yeast vacuoles!Does Koch’s postulates confirm it?)by Alipour and Gaeini,and the response“letter to the editor”(Candida accommodates nonculturable Helicobacter pylori in its vacuole-Koch’s postulates aren’t applicable)by Siavoshi and *** and Gaeini rejected the methods,results,discussion,and conclusions summarized in a review article by Siavoshi and *** present article reviews and discusses evidence on the evolutionary adaptation of Helicobacter pylori(***)to thrive in Candida cell vacuoles and concludes that Candida could act as a Trojan horse,transporting potentially infectious *** into the stomach of humans.

关键词： Helicobacter pylori Candida yeast Intracellular presence Helicobacter pylori-specific gene Helicobacter pylori transmission

Predictors of Adverse Pregnancy Outcomes Following Traumatic Injuries

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Current Medical Science 2024年第3期44卷 642-647页

作者： Wan-rong LU Ping WU Gong SONG mei-qi gu Zhe XU Li HE National Clinical Research Center for Gynecology and Obstetrics Cancer Biology Research CenterTongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430030China Department of Traumatic Surgery Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430030China

Objective After traumatic injury in pregnant women,providing timely and appropriate management for high-risk patients is crucial for both pregnant women and *** study aimed to identify risk factors that predict adverse pregnancy outcomes after traumatic *** A retrospective cohort study including 317 pregnant patients who experienced trauma was *** collected data included general demographics,injury mechanisms and adverse pregnancy *** were divided into two subgroups based on the absence or presence of trauma-related adverse pregnancy *** and multivariate logistic regressions were conducted to estimate the associations between clinical variables and adverse pregnancy *** A total of 41(12.93%)patients experienced adverse pregnancy outcomes within the first 24 h *** study revealed that age>35 years(OR=14.995,95%CI:5.024–44.755,P<0.001),third trimester trauma(OR=3.878,95%CI:1.343–11.204,P=0.012),abdominal pain(OR=3.032,95%CI:1.221–7.527,P=0.017),vaginal bleeding(OR=3.226,95%CI:1.093–9.523,P=0.034),positive scan in focused assessment with sonography for trauma(FAST)positive(OR=8.496,95%CI:2.825–25.555,P<0.001),9≤injury severity score(ISS)<16(OR=3.039,95%CI:1.046–8.835,P=0.041)and ISS≥16(OR=5.553,95%CI:1.387–22.225,P=0.015)increased the probability of posttraumatic adverse pregnancy *** age,gestational age at delivery,vaginal bleeding and positive FAST results were risk factors for abnormal *** Advanced maternal age,third trimester,and positive FAST results should alert multidisciplinary trauma teams to closely monitor patients to prevent adverse pregnancy outcomes.

关键词： adverse pregnancy outcomes predictive factors abnormal delivery trauma