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Chinese Journal of Structural Chemistry 2007年第2期26卷 184-188页

作者： LIU Bo LI Xiu-Mei cui yun-cheng FENG Ming Department of Chemistry Jilin Normal University Siping Jilin 136000 China Department of Chemistry Tonghua Teachers College Tonghua Jilin 134002 China

A metal-organic coordination polymer [Co（phen）（BDC）（H20）]n·0.5nH2BDC （H2BDC = terephthahc acid, phen = 1,10-phenanthrohne） has been hydrothermally synthesized and structurally characterized by elemental analysis, IR spectrum, TG and single-crystal X-ray diffraction. The complex crystallizes in triclinic, space group Pi with a = 9.771（3）, b =10.739（3）, c = 11.249（4）A, α = 75.946（3）, β = 65.306（3）, γ = 86.073（4）°, V = 1039.6（6）A^3, C24H17CON2O7, Mr= 504.33, Dc = 1.611 g/cm^3,μ（MoKα） = 0.878 mm^-1, F（000） = 516, Z= 2, the final R = 0.0547 and wR = 0.1138 for 2916 observed reflections （I 〉 2σ（I））. It exhibits a one-dimensional zigzag chain-like structure.

关键词： hydrothermal synthesis crystal structure coordination polymer

Simultaneous determination of typical toxic aldehydes formed during food frying and digestion using isotope dilution UHPLC-QqQ-MS/MS

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Grain & Oil Science and Technology 2024年第1期7卷 42-49页

作者： Feng Wang yun cui Dongjie Liu Charles Brennan Soottawat Benjakul Weiwei cheng Gengsheng Xiao Lukai Ma Key Laboratory of Green Processing and Intelligent Manufacturing of Lingnan Specialty Food of Ministry and Rural Affairs College of Light Industry and FoodZhongkai University of Agriculture and EngineeringGuangzhou 510225China School of Science Royal Melbourne Institute of Technology UniversityMelbourneAustralia International Center of Excellence in Seafood Science and Innovation Faculty of Agro-IndustryPrince of Songkla UniversitySongkhla 90110Thailand College of Food Science and Technology Zhejiang University of TechnologyHangzhou 310014China

An isotope dilution ultra-performance liquid chromatography-triple quadrupole mass spectrometry method was developed to simultaneously detect two typical kinds ofα,β-unsaturated aldehydes,namely 4-hydroxy-2-hexenal(4-HHE)and 4-hydroxy-2-nonenal(4-HNE),in *** proposed method exhibited a linear range of 10-1000 ng/mL with a limit of detection of 0.1-2.0 ng/g and a limit of quantification of 0.3-5.0 ng/*** recovery rates of these typical toxic aldehydes(i.e.,4-HHE,4-HNE)and their d3-labeled analogues were 91.54%-105.12%with a low matrix ***,this proposed method was successfully applied to a real frying system and a simulated digestion system,wherein the contents of 4-HHE and 4-HNE were determined for ***,the obtained results provide strong support for further research into the production of 4-HHE and 4-HNE resulting from foods during oil digestion and frying.

关键词： UHPLC-QqQ-MS/MS 4-Hydroxy-2-hexenal 4-Hydroxy-2-nonenal Frying Simulated digestion

Exponential Synchronization of Delayed Stochastic Complex Dynamical Networks via Hybrid Impulsive Control

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IEEE/CAA Journal of Automatica Sinica 2024年第3期11卷 785-787页

作者： Yao cui Pei cheng Xiaohua Ge the School of Mathematic Science Anhui UniversityHefei 230601China IEEE the School of Science Computing and Engineering TechnologiesSwinburne University of TechnologyMelbourne VIC 3122Australia

Dear Editor,This letter addresses the synchronization problem of a class of delayed stochastic complex dynamical networks consisting of multiple drive and response *** aim is to achieve mean square exponential synchronization for the drive-response nodes despite the simultaneous presence of time delays and stochastic noises in node dynamics.

关键词： dynamics stochastic letter

Hydrothermal Synthesis and Crystal Structure of a Cadmium(II) Polymer with One-dimensional Chain Structure: [Cd(bpy)(BDC)]_n·nbpy

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Chinese Journal of Structural Chemistry 2007年第5期26卷 537-540页

作者： LI Xiu-Mei NIU Yan-Ling WANG Qing-Wei cui yun-cheng LIUBo Department of Chemistry Tonghua Teachers College Tonghua Jilin 134002 China Jilin Normal University Siping Jilin 136000 China

A metal-organic coordination polymer [Cd（bpy）（BDC）]n·nbpy （bpy = 2,2-bipyri-dine, H2BDC = terephthalic acid） has been hydrothermally synthesized and structurally characterized by elemental analysis, IR spectrum, TG and single-crystal X-ray diffraction. The complex crystallizes in monoclinic, space group C2/c with a = 15.723（5）, b = 21.695（5）, c = 7.576（5） A, β = 116.171（7）°, V = 2319.3（18）A^3, C28H20CdN4O4, Mr = 588.88, Dc = 1.686 g/cm^3, μ（MoKα） = 0.987 mm^-1, F（000） = 1184, Z = 4, the final R = 0.0464 and wR = 0.0831 for 1882 observed reflections （Ⅰ〉 2σ（Ⅰ））. It exhibits a three-dimensional network with channels constructed from one-dimensional coordination chains via C–H…O hydrogen bonds and significant aromatic π-π stacking interactions.

关键词： hydrothermal synthesis crystal structure coordination polymer

Infiltration,runoff,and slope stability behaviors of infinite slope with macropores based on an improved Green–Ampt model

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Journal of Mountain Science 2024年第7期21卷 2220-2235页

作者： LI Shanghui WU Guoxiong QUE yun JIANG Zhenliang cheng Gaoyun College of Intelligent Construction Fuzhou University of International Studies and TradeFuzhou 350202China College of Civil Engineering Chongqing Jiao Tong UniversityChongqing 400074China Chongqing Vocational College of Architectural Engineering Chongqing 400072China College of Civil Engineering Fuzhou UniversityFuzhou 350000China Department of Civil and Environmental Engineering Hong Kong University of Science and TechnologyHong Kong 999077China T.Y.Lin International Engineering Consulting(China)Co.Ltd Chongqing 401120China

Infiltration–runoff–slope instability mechanism of macropore slope under heavy rainfall is *** paper studied its instability mechanism with an improved Green–Ampt(GA)model considering the dual-porosity(i.e.,matrix and macropore)and ponding condition,and proposed the infiltration equations,infiltration–runoff coupled model,and safety factor calculation *** show that the infiltration processes of macropore slope can be divided into three stages,and the proposed model is rational by a comparative *** wetting front depth of the traditional unsaturated slope is 17.2%larger than that of the macropore slope in the early rainfall stage and 27%smaller than that of the macropore slope in the late rainfall ***,macropores benefit the slope stability in the early rainfall but not in the *** flow does not occur initially but becomes pronounced with increasing rainfall *** equal depth of the wetting front in the two domains is regarded as the onset criteria of macropore *** analysis shows that macropore flow is delayed by increasing proportion of macropore domain(ω_(f)),whereas promoted by increasing ratio of saturated permeability coefficients between the two domains(μ).The increasing trend of ponding depth is sharp at first and then grows ***,when rainfall duration is less than 3 h,ωf andμhave no significant effect on the safety factor,whereas it decreases with increasingωf and increases with increasingμunder longer duration(≥3 h).With the increase ofω_(f),the slope maximum instability time advances by 10.5 h,and with the increase ofμ,the slope maximum instability time delays by 3.1 h.

关键词： Macropore slope Green–Ampt infiltration model Equivalent wetting front Ponding response time Slope stability

Failure mechanism and infrared radiation characteristic of hard siltstone induced by stratification effect

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Journal of Mountain Science 2024年第3期21卷 1058-1074页

作者： cheng yun SONG Zhanping XU Zhiwei YANG Tengtian TIAN Xiaoxu School of Civil Engineering Yancheng Institute of TechnologyYancheng 224051China School of Civil Engineering Xi'an University of Architecture and TechnologyXi'an 710055China Shaanxi Key Laboratory of Geotechnical and Underground Space Engineering Xi'an 710055China China Railway Construction Bridge Engineering Bureau Group Co. Ltd.Tianjin 300300China

The deformation in sedimentary rock induced by train loads has potential threat to the safe operation of tunnels. This study investigated the influence of stratification structure on the infrared radiation and temporal damage mechanism of hard siltstone. The uniaxial compression tests, coupled with acoustic emission(AE) and infrared radiation temperature(IRT) were conducted on siltstones with different stratification effects. The results revealed that the stratigraphic structure significantly affects the stress-strain response and strength degradation characteristics. The mechanical parameters exhibit anisotropy characteristics, and the stratification effect exhibits a negative correlation with the cracking stress and peak stress. The failure modes caused by the stratification effect show remarkable anisotropic features, including splitting failure(Ⅰ: 0°-22.50°, Ⅱ: 90°), composite failure(45°), and shearing failure(67.50°). The AE temporal sequences demonstrate a stepwise response characteristic to the loading stress level. The AE intensity indicates that the stress sensitivity of shearing failure and composite failure is generally greater than that of splitting failure. The IRT field has spatiotemporal migration and progressive dissimilation with stress loading and its dissimilation degree increases under higher stress levels. The stronger the stratification effect, the greater the dissimilation degree of the IRT field. The abnormal characteristic points of average infrared radiation temperature(AIRT) variance at local stress drop and peak stress can be used as early and late precursors to identify fracture instability. Theoretical analysis shows that the competitive relationship between compaction strengthening and fracturing damage intensifies the dissimilation of the infrared thermal field for an increasing stress level. The present study provides a theoretical reference for disaster warnings in hard sedimentary rock mass.

关键词： Hard siltstone Failure mechanism Stratification effect Infrared radiation characteristic Temporal-damage mechanism Dissimilation

Endosulfan residues and farmers’replacement behaviors of endosulfan in the north-west inland cotton region

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Frontiers of Environmental Science & Engineering 2024年第4期18卷 35-47页

作者： Shuyan Zhou Yang Zhang Jingjing Wang Shikun cheng Fuyan Zhuo yun Hong School of Energy and Environmental Engineering University of Science and Technology Beijing 100083China Foreign Environmental Cooperation Center Ministry of Ecology and Environment of the People’s Republic of ChinaBeijing 100035China United Nations Development Programme in China Beijing 100600China National Agro-Tech Extension and Service Center Beijing 100125China

We assessed the situation of endosulfan residues in cotton fields after the endosulfan ban came into effect and the current knowledge,attitude,and practice(KAP)of cotton farmers on the phase-out of endosulfan and the application of alternative *** samples(n=91)of cotton fields were collected from the major cotton-producing areas in China,namely the north-west inland cotton region,and the endosulfan residues were analyzed.A KAP survey was carried out for cotton farmers,and 291 questionnaires were *** influences of gender,age,education background,cotton planting years,publicity and training,income sources,and other factors on cotton farmers’KAP were *** results showed that endosulfan sulfate was the main endosulfan residue in the soil,followed byβ-endosulfan andα-endosulfan,the average residual contents were 0.569,0.139,and 0.060μg/kg,*** results of the KAP study showed that cotton farmers scored low on knowledge about the phase-out of endosulfan and the application of alternative technologies but high on attitude and *** number of family members,years of cotton planting,age,and the cottonplanting area had different degrees of influence on KAP *** training could significantly improve the KAP scores of cotton farmers;training should be more targeted and designed reasonably for key groups,such as men and the population under 30,followed by training them to use pesticides *** large-scale cotton growers,training should focus on green prevention and control technologies.

关键词： Cotton fields Endosulfan residues Farmers KAP survey Replacement behaviours

Prediction of mechanical ventilation outcome by early abdominal-visceral-blood-flow-and-function score in critically ill patients after cardiopulmonary bypass in the ICU: A prospective observational study

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Journal of Intensive Medicine 2024年第1期4卷 101-107页

作者： Chaofu Yue Longxiang Su Jun Wang Na cui Yuankai Zhou Wei cheng Bo Tang Xi Rui Huaiwu He yun Long Department of Intensive Care Unit Peking Union Medical College HospitalBeijingChina Department of Intensive Care Unit Qujing First People’s HospitalQujingYunnanChina Department of Intensive Care Unit Shiyan People’s Hospital of Bao’an DistrictShenzhenGuangdongChina

Background:Abdominal organs are important organs that sense and respond to ischemia and hypoxia,but there are few evaluation *** use ultrasonography to evaluate abdominal organ function and blood flow in patients with mechanical ventilation(MV)after cardiopulmonary bypass and to obtain a semiquantitative score for abdominal organ function and blood ***:Patients with cardiopulmonary bypass in the Critical Care Department of Peking Union Medical College Hospital in China from March to July 2021 were enrolled in this prospective observational *** correlation of the abdominal-visceral-blood-flow-and-function score(AVBFS)with the duration of MV,number of days spent in the intensive care unit(ICU),acute physiology and chronic health evaluation II(APACHE-II),sequential organ failure assessment(SOFA),lactate,epinephrine,and norepinephrine use was analyzed,and the results were used to assess the predictive value of the receiver operating characteristic curve(ROC)regression analysis score for the duration of ***:Of the 92 patients who underwent cardiopulmonary bypass,41 were finally *** AVBFS were significantly correlated with the duration of MV,number of days spent in the ICU,APACHE-II score,SOFA score,and norepinephrine use *** AVBFS in a group of patients using ventilators≥36 h were significantly higher than those obtained for a group of patients using ventilators<36 h(P<0.05).The evaluation results for the AVBFS at 0-12 h after ICU admission were as follows:area under the ROC curve(AUC)=0.876(95%confidence interval[CI]:0.767 to 0.984),cut-off value=2.5,specificity=0.842,and sensitivity=***:Abdominal visceral organ function and blood perfusion can be used to evaluate gastrointestinal *** is related to early and late extubation after cardiac surgery.

关键词： Ultrasonic evaluation Abdominal-visceral-blood-flow-and-function score(AVBFS) Gastrointestinal dysfunction Mechanical ventilation Cardiopulmonary bypass

High-resolution remote thermometry based on Bi^(3+)-doped 0D zinc halide hybrids

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Science China Chemistry 2024年第8期67卷 2599-2605页

作者： cui-Mi Shi Shu-Hua Xue Jin-yun Wang Liang-Jin Xu Zhong-Ning Chen State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China Fujian Science Technology Innovation Laboratory for Optoelectronic Information of ChinaFuzhou 350108China University of Chinese Academy of Sciences Beijing 100049China

Developing highly sensitive optical thermometers is of great significance due to their capability to enable remote and non-contact temperature measurements, rendering them highly applicable in diverse and harsh environments. Herein we report a temperature-dependent phosphor of 0D metal halide hybrid by incorporating Bi^(3+)into the(MePPh_(3))_(2)ZnCl_(4) matrix. Through Bi^(3+)doping,the initially non-luminescent(MePPh_(3))_(2) ZnCl_(4) matrix exhibits a deep-blue emission centered at 453 nm, with a photoluminescence quantum yield(PLQY) of 5.71% and a Stokes shift of 75 nm at room temperature. Experimental characterization demonstrates that exciton-like luminescence of Bi^(3+)is mainly responsible for the blue emission. Single crystals of Bi^(3+)-doped(MePPh_(3))_(2)ZnCl_(4) show an unusual correlation between photoluminescence(PL) lifetime and temperature. Particularly, the dependence of luminescence lifetime on temperature is most remarkable in the temperature range of 80 to 100 K with an exceptional sensitivity up to 0.09 K^(-1), representing one of the best levels for thermometry based on PL decay lifetime. Our work not only provides a viable strategy for designing a novel, environmentally friendly, and stable blue emitter, but also paves the way for precise thermometric application at low temperature.

关键词： lead-free hybrids Bi^(3+)doping blue emission temperature sensing

Molecular simulation study on the evolution process of hydrate residual structures into hydrate

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Chinese Journal of Chemical Engineering 2024年第5期69卷 79-91页

作者： Liwei cheng yunfei Li Jinlong cui Huibo Qin Fulong Ning Bei Liu Guangjin Chen Faculty of Engineering China University of GeosciencesWuhan 430074China State Key Laboratory of Heavy Oil Processing China University of PetroleumBeijing 102249China College of Science Nanchang Institute of TechnologyNanchang 330099China School of Chemical Engineering Guangdong University of Petrochemical TechnologyMaoming 525000China National Center for International Research on Deep Earth Drilling and Resource Development China University of Geosciences(Wuhan)Wuhan 430074China

The clathrate hydrate memory effect is a fascinating phenomenon with potential applications in carbon capture,utilization and storage(CCUS),gas separation,and gas storage as it can accelerate the secondary formation of clathrate ***,the underlying mechanism of this effect remains *** gain a better understanding of the mechanism,we conducted molecular dynamic simulations to simulate the initial formation and reformation processes of methane *** this work,we showed the evolution process of hydrate residual structures into hydrate *** simulation results indicate that the residual structures are closely related to the existence of hydrate memory effect,and the higher the contribution of hydrate dissociated water to the hydrate nucleation process,the faster the hydrate *** hydrate dissociation,the locally ordered structures still exist after hydrate dissociation and can promote the formation of cluster structures,thus accelerating hydrate ***,the nucleation process of hydrate and the formation process of clusters are *** size of clusters composed of cup-cage structures is critical for hydrate *** residence time at high temperature after hydrate decomposition will affect the strength of the hydrate memory *** simulation results provide microscopic insights into the occurrence of the hydrate memory effect and shed light on the hydrate reformation process at the molecular scale.

关键词： Memory effect Molecular simulation Hydrate reformation Residual structures