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Comprehensive Suitability Evaluation of Tea Crops Using GIS and a Modified Land Ecological Suitability Evaluation Model

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Pedosphere 2012年第1期22卷 122-130页

作者： LI Bo ZHANG feng ZHANG Li-Wen HUANG jing-feng jin zhi-feng D.K.GUPTA College of Public Administration Zhejiang UniversityHangzhou 310058(China) Institute of Agricultural Remote Sensing and Information Technology Zhejiang UniversityHangzhou 310058(China) Zhejiang Climatic Centre Zhejiang Meteorological BureauHangzhou 310017(China) Departamet of Biochemistry Molecular Cell Biology of Plant Experimental InstitutionGranada(Spain)

Tea （Camellia sinensis） is one of the most valuable cash crops in southern China; however, the planting distribution of tea crops is not optimal and the production and cultivation regions of tea crops are restricted by law and custom. In order to evaluate the suitability of tea crops in Zhejiang Province, the annual mean temperature, the annual accumulated temperature above 10 ℃, the frequency of extremely low temperature below -13 ℃, the mean humidity from April to October, slope, aspect, altitude, soil type, and soil texture were selected from climate, topography, and soil factors as factors for land ecological evaluation by the Delphi method based on the ecological characteristics of tea crops. These nine factors were quantitatively analyzed using a geographic information system （GIS）. The grey relational analysis （GRA） was combined with the analytic hierarchy process （AHP） to address the uncertainties during the process of evaluating the traditional land ecological suitability, and a modified land ecological suitability evaluation （LESE） model was built. Based on the land-use map of Zhejiang Province, the regions that were completely unsuitable for tea cultivation in the province were eliminated and then the spatial distribution of the ecological suitability of tea crops was generated using the modified LESE model and GIS. The results demonstrated that the highly, moderately, and non-suitable regions for the cultivation of tea crops in Zhejiang Province were 27552.66, 42 724.64, and 26507.97 km2, and accounted for 28.47%, 44.14%, and 27.39% of the total evaluation area, respectively. Validation of the method showed a high degree of coincidence with the current planting distribution of tea crops in Zhejiang Province. The modified LESE model combined with GIS could be useful in quickly and accurately evaluating the land ecological suitability of tea crops, providing a scientific basis for the rational distribution of tea crops and acting as a reference to land pol

关键词： analytic hierarchy process (AHP) grey relational analysis (GRA) soil temperature topography

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基于Pt-PDDA/还原石墨烯纳米电极材料的构建及电化学检测4-氨基苯酚

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化学试剂 2024年第4期46卷 108-113页

作者：智晋峰郝玺龙白雅蓉梁文婷山西大学环境科学研究所山西太原030006 山西省科技情报与战略研究中心山西太原030024

通过Hummer法将天然石墨粉氧化得到氧化石墨,再将其超声分散于去离子水中形成稳定的氧化石墨分散液。为了引入铂粒子并使之与氧化石墨烯片牢固锚定,将氧化石墨分散液与氯铂酸溶液混,合成Pt-PDDA/还原石墨烯(Pt NPs-PDDA/rGO)纳米电极材... 详细信息

通过Hummer法将天然石墨粉氧化得到氧化石墨,再将其超声分散于去离子水中形成稳定的氧化石墨分散液。为了引入铂粒子并使之与氧化石墨烯片牢固锚定,将氧化石墨分散液与氯铂酸溶液混,合成Pt-PDDA/还原石墨烯(Pt NPs-PDDA/rGO)纳米电极材料。通过红外、紫外光谱分析以及扫描循环伏安曲线、交流阻抗曲线对该复合电极材料进行了表征。由于铂优良的催化性能,聚二烯丙基二甲基氯化铵(PDDA)的防聚合功能,石墨烯巨大的表面积、优异的电子传导性能及对4-氨基苯酚(4-AP)强大的吸附作用,将制备得到的Pt-PDDA/还原石墨烯纳米电极材料构建电化学传感器,用于对4-AP超灵敏的检测。结果表明,在0.5 mol/L的磷酸盐缓冲液(PBS)中对不同浓度的4-AP进行测定,Pt NPs-PDDA/rGO复合膜修饰的GCE与裸露的GCE和功能化石墨烯(PDDA-rGO)修饰的GCE相比,4-AP的氧化还原峰电流显著增加,表明Pt NPs-PDDA/rGO具有对4-AP的电催化活性。然后对实验条件进行了优化,研究了不同实验条件对电化学传感器性能的影响。结果表明,在最理想的条件下,4-AP浓度在1.00×10^(-5)~1.00×10^(-3)mol/L范围内时,氧化峰电流与浓度呈良好的线性关系,相关系数为0.992 2。最后将其应用于河水和自来水中的4-AP检测,获得令人满意的结果,回收率为98.0%~106.0%。

关键词：电化学 4-氨基苯酚玻碳电极铂催化剂

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Graphdiyne(C_(n)H_(2n-2))as an"electron transfer bridge"boosting photocatalytic hydrogen evolution over Zn_(0.5)Co_(0.5)S/MoS_(2)S-scheme heterojunction

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Rare Metals 2024年第5期43卷 1999-2014页

作者： Mei Li jing-zhi Wang zhi-Liang jin School of Chemistry and Chemical Engineering North Minzu UniversityYinchuan 750021China School of Chemistry and Chemical Engineering Ningxia Key Laboratory of Solar Chemical Conversion TechnologyKey Laboratory for Chemical Engineering and TechnologyState Ethnic Affairs CommissionNorth Minzu UniversityYinchuan 750021China

In the process of photocatalytic water cracking,the migration rate and utilization rate of photogenerated charges determine the hydrogen evolution performance of the *** this paper,a carbon isotope superconducting material graphdiyne(GDY)is prepared by mechanical ball milling and introduced into the S-scheme heterojunction Zn_(0.5)Co_(0.5)S/MoS_(2)inorganic *** terms of hydrogen evolution kinetics,GDY acts as an electron bridge,not only accelerating the migration of photogenerated carriers but also improving the utilization of photogenerated ***,the large twodimensional layer provides more loading and anchoring points for Zn_(0.5)Co_(0.5)S/MoS_(2),which increases the number of active *** ternary composite catalyst 20%GDY/Zn_(0.5)Co_(0.5)S/MoS_(2)(20-GCSM)generates 69.94μmol of hydrogen(5 h)in triethanolamine *** is 2.97 and1.80 times higher than Zn_(0.5)Co_(0.5)S and Zn_(0.5)Co_(0.5)S/MoS_(2),*** the cyclic experiment,it still has stable hydrogen evolution performance after standing for24 h(under dark conditions).In addition,the potential mechanism of photocatalytic hydrogen evolution is demonstrated through in-situ X-ray photoelectron *** work provides a reference for further research in the field of introducing carbon materials into photocatalytic systems and improving the utilization of photogenerated charges.

关键词： Graphdiyne S-scheme heterojunction Electron transfer bridge Hydrogen production

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Internal limiting membrane peeling combined with silicone oil or air tamponade for highly myopic foveoschisis

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International Journal of Ophthalmology(English edition) 2024年第6期17卷 1079-1085页

作者： jin Deng Wen-Tao Sun Ke Gong Li-Ping Wang feng-zhi Li Xi’an People’s Hospital(Xi’an Fourth Hospital) Shaanxi Eye HospitalAffiliated People’s Hospital of Northwest UniversityXi’an 70004Shaanxi ProvinceChina

AIM:To compare the efficacy of pars plana vitrectomy(PPV)combined with internal limiting membrane(ILM)and silicone oil or sterile air tamponade for the treatment of myopic foveoschisis(MF)in highly myopic ***:This retrospective study included 48 myopic eyes of 40 patients with MF and axial lengths(ALs)ranging from 26-32 mm treated between January 2020 and January *** patients were underwent PPV combined with ILM peeling followed by sterile air or silicone oil tamponade and followed up at least *** on the features on spectral-domain optical coherence tomography(SD-OCT),the eyes were divided into the MF-only group(Group A,n=15 eyes),MF with central foveal detachment group(Group B,n=20 eyes),and MF with lamellar macular hole group(Group C,n=13 eyes).According to AL,eyes were further divided into three groups:Group D(26.01-28.00 mm,n=12 eyes),Group E(28.01-30.00 mm,n=26 eyes),and Group F(30.01-32.00 mm,n=10 eyes).The best-corrected visual acuity(BCVA),central foveal thickness(CFT),and complications were ***:The patients included 16 males and 24 females with the mean age of 56±*** BCVA and CFT improved in all groups after surgery(P0.05).The intergroup differences of BCVA and CFT postoperatively were statistically significant in Group D,E,and *** eyes were injected with sterile air,and 28 eyes were injected with silicone oil for tamponade based on the ***,there was no statistically significant difference among Groups D,E,and F in terms of the results of sterile air or silicone oil *** mean recovery time was 5.9mo for MF patients subjected to silicone oil tamponade and 7.7mo for patients subjected to sterile air tamponade,and the difference was not statistically ***:PPV and ILM peeling combined with silicone oil or sterile air tamponade can achieve good results for MF in highly myopic eyes with ALs

关键词： axial length myopic foveoschisis highly myopic internal limiting membrane pars plana vitrectomy

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Quantum phase transition of the Jaynes-Cummings model

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Science China(Physics,Mechanics & Astronomy) 2024年第1期67卷 1-9页

作者： Cheng Liu jin-feng Huang Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education Key Laboratory for Matter Microstructure and Function of Hunan ProvinceDepartment of Physics and Synergetic Innovation Center for Quantum Effects and ApplicationsInstitute of Interdisciplinary StudiesHunan Normal UniversityChangsha 410081China

Herein,we propose an experimentally feasible scheme to show the quantum phase transition of the Jaynes-Cummings(JC)model by modulating the transition frequency of a two-level system in a quantum Rabi model with strong *** tuning the modulation frequency and amplitude,the ratio of the effective coupling strength of the rotating terms to the effective cavity(atomic transition)frequency can enter the deep-strong coupling regime,while the counter-rotating terms can be ***,a deep-strong JC model is *** ratio of the coupling strength to resonance frequencies in the deep-strong JC model is two orders of magnitude larger than the corresponding ratio in the original quantum Rabi *** scheme can be employed in atom-cavity resonance and off-resonance cases,and it is valid over a broad *** nonzero average cavity photons of the ground state indicate the emergence of a quantum phase ***,we demonstrate the dependence of the phase diagram on the atom-cavity detuning and modulation *** the parameters used in our scheme are within the reach of current experimental *** scheme provides a new mechanism for investigating the critical phenomena of finite-sized systems without requiring classical field limits,thereby opening a door for studying fundamental quantum phenomena occurring in the ultrastrong and even deep-strong coupling regimes.

关键词： Jaynes-Cummings model quantum phase transition frequency modulation

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Simultaneous purification of minor components in natural products using twin-column recycling chromatography with a step solvent gradient

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Chinese Journal of Chemical Engineering 2024年第5期69卷 212-219页

作者： Guangxia jin Yuxue Wu feng Wei School of Biological and Chemical Engineering NingboTech UniversityNingbo 315100China

The isolation of minor components from complex natural product matrices presents a significant challenge in the field of purification science due to their low concentrations and the presence of structurally similar *** study introduces an optimized twin-column recycling chromatography method for the efficient and simultaneous purification of these elusive *** introducing water at a small flowing rate between the twin columns,a step solvent gradient is created,by which the leading edge of concentration band would migrate at a slower rate than the trailing edge as it flowing from the upstream to downstream ***,the band broadening is counterbalanced,resulting in an enrichment effect for those minor components in separation ***,two target substances,which showed similar peak position in high performance liquid chromatography(HPLC)and did not exceed 1.8%in crude paclitaxel were selected as target compounds for *** using the twin-column recycling chromatography with a step solvent gradient,a successful purification was achieved in getting the two with the purity almost 100%.We suggest this method is suitable for the separation of most components in natural produces,which shows higher precision and recovery rate compared with the common lab-operated separation ways for natural products(thin-layer chromatography and prep-HPLC).

关键词： Solvent gradient Twin-column recycling chromatography Purification Minor component Natural products

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Flocking of a Cucker–Smale Type Model with Compactly Supported Interaction Functions

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Acta Mathematica Sinica,English Series 2024年第9期40卷 2285-2296页

作者： Chun Yin jin Shuang zhi LI College of Science China Agricultural UniversityBeijing 100083P.R.China

How to analyze flocking behaviors of a multi-agent system with local interaction functions is a challenging problem in *** and Tadmor in 2011 also stressed the significance to assume that the interaction function is rapidly decaying or cut-off at a finite distance(*** and Tadmor in ***.2011).In this paper,we study the flocking behavior of a Cucker–Smale type model with compactly supported interaction *** properties of a connected stochastic matrix,together with an elaborate analysis on perturbations of a linearized system,we obtain a sufficient condition imposed only on model parameters and initial data to guarantee ***,it is shown that the system achieves flocking at an exponential rate.

关键词： Cucker-Smale model local interaction flocking stochastic matrix neighbor graph

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Multimorbidity and mortality among older patients with coronary heart disease in Shenzhen,China

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Journal of Geriatric Cardiology 2024年第1期21卷 81-89页

作者： Fu-Rong LI Shuang WANG Xia LI zhi-Yuan CHENG Cheng jin Chun-Bao MO jing ZHENG feng-Chao LIANG Dong-feng GU Shenzhen Key Laboratory of Cardiovascular Health and Precision Medicine Southern University of Science and TechnologyShenzhenGuangdongChina School of Public Health and Emergency Management Southern University of Science and TechnologyShenzhenGuangdongChina Shenzhen Health Development Research and Data Management Center ShenzhenChina School of Medicine Southern University of Science and TechnologyShenzhenGuangdongChina

BACKGROUND The current understanding of the magnitude and consequences of multimorbidity in Chinese older adults with coronary heart disease(CHD)is *** aimed to assess the association and population-attributable fractions(PAFs)between multimorbidity and mortality among hospitalized older patients who were diagnosed with CHD in Shenzhen,*** We conducted a retrospective cohort study of older Chinese patients(aged≥65 years)who were diagnosed with *** proportional hazards models were used to estimate the associations between multimorbidity and all-cause and cardiovascular disease(CVD)*** also calculated the *** The study comprised 76,455 older hospitalized patients who were diagnosed with CHD between January 1,2016,and August 31,*** them,70,217(91.9%)had multimorbidity,defined as the presence of at least one of the predefined 14 chronic *** with cancer,hemorrhagic stroke and chronic liver disease had the worst overall death risk,with adjusted HRs(95%CIs)of 4.05(3.77,4.38),2.22(1.94,2.53),and 1.85(1.63,2.11),*** CVD mortality,the highest risk was observed for hemorrhagic stroke,ischemic stroke,and chronic kidney disease;the corresponding adjusted HRs(95%CIs)were 3.24(2.77,3.79),1.91(1.79,2.04),and 1.81(1.64,1.99),***-cause mortality was mostly attributable to cancer,heart failure and ischemic stroke,with PAFs of 11.8,10.2,and 9.1,*** for CVD mortality,the leading PAFs were heart failure,ischemic stroke and diabetes;the corresponding PAFs were 18.0,15.7,and 6.1,*** Multimorbidity was common and had a significant impact on mortality among older patients with CHD in Shenzhen,***,heart failure,ischemic stroke and diabetes are the primary contributors to ***,prioritizing improved treatment and management of these comorbidities is essential for the survival prognosis of CHD patients from a holistic public health perspective.

关键词： patients morbidity mortality

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Combustion mechanism of benzene in iron ore sintering process:experimental and simulation

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Journal of Iron and Steel Research International 2024年第1期31卷 195-203页

作者： zhi-gang Que jin-ming Shi Xian-bin Ai Institute of Energy Research Jiangxi Academy of ScienceNanchang330096JiangxiChina Jiangxi Carbon Neutralization Research Center Nanchang330096JiangxiChina

Benzene is a typical component of volatile organic compounds(VOCs)in the iron ore sintering flue *** combustion behavior of benzene directly affects the emission of VOCs in iron ore sintering *** effects of temperature,benzene,and oxygen concentrations on the conversion ratio of benzene were investigated by experiments and numerical *** experiments were carried out in a tube reactor at temperatures of 773-1098 K,benzene concentrations of 0.01-0.03 vol.%,and oxygen concentrations of 10-21 vol.%.The numerical simulation was performed with the plug flow model in the CHEMKIN program based on a kinetic model that consists of 132 chemical species and 772 elementary step-like *** experimental results reveal that increasing the temperature and benzene concentration could signifi-cantly promote benzene *** is attributed to the increase in the reaction rates of all steps in the pathway for forming CO_(2)and H_(2)*** addition,due to the large equivalent ratio of oxygen to benzene,the conversion ratio of benzene remained constant at different oxygen *** simulation results were in good agreement with the experimental results and indicated that six elementary reactions dominated the formations of CO_(2)and H_(2)*** oxidations of C_(6)H_(5)O,CO,and C_(5)H_(4)O intermediates to CO_(2)were the limiting steps in the reaction pathways.

关键词： Benzene Volatile organic compound Iron ore sinter Combustion Simulation Temperature Oxygen

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Hierarchical V_(3)S_(4)/C nanofibers with fast kinetics for superior alkali metal batteries

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Rare Metals 2024年第4期43卷 1836-1844页

作者： Li Chen zhi-Xin Rao zhi Chen Zhao-Hui Wu Shuai Yang zhi-Jun feng Hui-Yong Yang Fan-Yan Zeng Xi-Bao Li jin-Yang Hu Jun-Tong Huang School of Materials Science and Engineering Nanchang Hangkong UniversityNanchang330063China School of Aeronautical Manufacturing Engineering Nanchang Hangkong UniversityNanchang330063China

Owing to the numerous benefits,including low cost and great theoretical capacity,V3S4 has been a research hotspot for Li^(+)/Na^(+)/K^(+) ***,the V_(3)S_(4) electrode with long cycling stability and high specific capacities continues to pose significant *** this work,vacuum vulcanization is combined with electrospinning to synthesize V_(3)S_(4)/C composite nanofibers(V_(3)S_(4)@CNF).

关键词： composite fibers kinetics

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