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Multicomponent remote C(sp^(2))–H bond addition by Ru catalysis:An efficient access to the alkylarylation of 2H-imidazoles

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Chinese Chemical Letters 2024年第10期35卷 257-261页

作者： Yi Luo lin dong Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Sichuan Province Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial TechnologyWest China School of PharmacySichuan UniversityChengdu 610041China

Sequential C–H bond addition with two different coupling partners is a powerful method for the rapid and modular construction of complex molecules based on simple starting ***,an efficient ruthenium-catalysed multicomponent long-range C–H functionalization of 2H-imidazoles was *** protocol showed good substrate suitability and yielded alkyl arylation products with potential biological activity.

关键词： Remote C-H functionalization Multi-component reaction Ruthenium catalysis 2H-Imidazoles

Numerical Simulation of Electromagnetic Force in Double-Sided Arc Welding Process

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Journal of Materials Science & Technology 2003年第z1期19卷 223-224页

作者： Hongming GAO lin WU Honggang dong State Key Lab. of Advanced Welding Production Technology Harbin Institute of Technology Harbin 150001 China State Key Lab. of Advanced Welding Production Technology Harbin Institute of Technology Harbin 150001 China State Key Lab. of Advanced Welding Production Technology Harbin Institute of Technology Harbin 150001 China

Up till now, most of the researchers believe that there are four kinds of forces in the weld pool convection, they aresurface tension, electromagnetic force, buoyancy and gas shear stress. So electromagnetic force is very important,especially when large current is applied. In most of previous models, the electromagnetic force is calculated analytically,in which only the axial component of current is considered. Actually the radial component of current has thesame effect, and may be advanced in some locations. In double-sided arc welding process, instead of the earthclamp, another torch is placed on the opposite side; the current will go from one torch, through the weld zone,to another torch. In this case, the current is more concentrated in the weld zone; the electromagnetic force willhave significant effect compared with conventional welding process. In this paper, a new method of numericalcalculation for electromagnetic force is developed, in which both axial and radial components are considered. And asan example, the distribution of electromagnetic force in double-sided arc welding is calculated. It demonstrates thatthis new method could give more accurate simulation of electromagnetic force, and is close to the actual process.

关键词： Electromagnetic force, Numerical simulation, Double-sided arc welding process

Synthesis,Crystal Structure and Photoluminescence of a One-dimensional Zinc(Ⅱ)Coordination Polymer with Substituted Terpyridine

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Chinese Journal of Structural Chemistry 2010年第7期29卷 1098-1102页

作者： GOU Lei LI dong-lin School of Materials Science and Engineering Chang'an University Xi'an Shaanxi 710061 China College of Chemistry and Materials Science Northwest University Xi'an Shaanxi 710069 China

The title compound, [Zn（4-pytpy）（NO3）2] （4-pytpy = 4′-（4-pyridyl）-2,2′：6′,2＂- terpyridine） 1, has been synthesized by the solvothermal reaction of Zn（NO3）2·6H2O with 4-pytpy in CH3OH solution. It crystallizes in the triclinic system, space group P1 with a = 8.358（6）, b = 11.121（8）, c = 11.374（8）A, α = 74.226（11）, β = 74.532（11）, γ = 83.085（12）°, Mr= 499.74, V= 979.3（12） A3, Z = 2, Dc = 1.695 g/cm3, F（000） = 508,μ = 1.309 mm^-1, the final R = 0.0547 and wR = 0.1588. X-ray crystal structure analysis revealed that the Znn is hexa-eoordinated by two oxygen atoms from two nitrate groups and four nitrogen atoms, three of which are from the tridentate domain of one 4-pytpy and the other from the monodentate domain of another 4-pytpy. 4-pytpy as a bridging ligand connects ZnⅡ into a one-dimensional coordination polymer.

关键词： zinc(Ⅱ) complex crystal structure terpyridine,solvothermal reaction luminescentproperty

Sensor node-assisted asynchronous cooperative spectrum sensing for cognitive radio network

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The Journal of China Universities of Posts and Telecommunications 2014年第5期21卷 17-23页

作者： CAO Kai-tian WANG dong-lin Key Laboratory of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications National Mobile Communications Research Laboratory Southeast University Department of Electrical and Computer Engineering New York Institute of Technology (Nanjing Campus)

In order to take advantage of the asynchronous sensing information, alleviate the sensing overhead of secondary users （SUs） and improve the detection performance, a sensor node-assisted asynchronous cooperative spectrum sensing （SN-ACSS） scheme for cognitive radio （CR） network （CRN） was proposed. In SN-ACSS, each SU is surrounded by sensor nodes （SNs）, which asynchronously make hard decisions and soft decisions based on the Bayesian fusion rule instead of the SU. The SU combines these soft decisions and makes the local soft decision. Finally, the fusion center （FC） fuses the local soft decisions transmitted from SUs with different weight coefficients to attain the final soft decision. Besides, the impact of the statistics of licensed band occupancy on detection performance and the fact that different SNs have different sensing contributions are also considered in SN-ACSS scheme. Numerical results show that compared with the conventional synchronous cooperative spectrum sensing （SCSS） and the existing ACSS schemes, SN-ACSS algorithm achieves a better detection performance and lower cost with the same number of SNs.

关键词： cognitive radio asynchronous cooperative spectrum sensing Bayesian fusion rule ON-OFF model soft decision

Preparation of calcium carbonate particles coated with titanium dioxide

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International Journal of Minerals,Metallurgy and Materials 2009年第5期16卷 592-597页

作者： Hai lin Ying-bo dong Le-yong Jiang School of Civil and Environmental Engineering University of Science and Technology Beijing Beijing 100083 China

The preparation of a new mineral composite material, calcium carbonate particles coated with titanium dioxide, was studied. The mechanism of the preparation process was proposed. The new mineral composite material was made by the mechanoehemieal method under the optimum condition that the mass ratio of calcium carbonate particles to titanium dioxide was 6.5：3.5. The mass ratios of two different types of titanium dioxide （anatase to rutile） and grinding media to grinded materials were 8：2 and 4：1 respectively, and the modified density was 60%. Under this condition, the new material was capable of forming after 120-min modification. The hiding power and oil absorption of this new material were 29.12 g/m^2 and 23.30%, respectively. The results show that the modification is based on surface hydroxylation. After coating with titanium dioxide, the hiding power of calcium carbonate can be improved greatly. The new mineral composite materials can be used as the substitute for titanium dioxide.

关键词： calcium carbonate mechano-chemical process titanium dioxide film hydroxylation

A soft-contact hybrid electromagnetic–triboelectric nanogenerator for self-powered water splitting towards hydrogen production

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Nano Research 2024年第7期17卷 6567-6574页

作者： Fuxue Ma Yingjie Wu Shuge Dai Pei lin Junlu Sun lin dong Key Laboratory of Material Physics of Ministry of Education and School of Physics and MicroelectronicsZhengzhou UniversityZhengzhou 450000China

The effective acquisition of hydrogen energy from the ocean offers a promising sustainable solution for increasing global energy ***,a self-powered high-efficient hydrogen generation system is proposed by integrating a triboelectric–electromagnetic hybrid nanogenerator(TEHG),power management circuit(PMC),and an electrolytic *** the wind triggering,as-fabricated TEHG can effectively convert breeze energy into electric energy,which demonstrates a high output current of 20.3 mA at a speed rotation of 700 rpm and the maximal output power of 13.8 mW at a load of 10 MΩ.Remarkably,asdesigned self-powered system can perform a steady and continuous water splitting to produce hydrogen(1.5μL·min^(−1))by adding a matching capacitor between the PMC and electrolytic *** the circuit,the capacitor can not only function as a charge compensation source for water splitting,but also stabilize the working *** other self-powered water splitting systems,the proposed system does not need catalysts or the complex electrical energy storage/release process,thus improving the hydrogen production efficiency and reducing the *** work provides an effective strategy for clean hydrogen energy production and demonstrates the huge potential of the constructed self-powered system toward carbon neutralization.

关键词： wind energy harvester hybrid nanogenerator energy conversion and management hydrogen energy production

Observation and modeling on irregular purple soil water infiltration process

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Journal of Mountain Science 2017年第6期14卷 1076-1085页

作者： CHENG dong-bing dong lin-yao QIAN Feng SUN Bei Changjiang River Scientific Research Institute Changjiang Water Resources Commission Wuhan 430010 China

The infiltration process is a critical link between surface water and groundwater. In this research, a specific device to observe infiltration processes in homogeneous and heterogeneous soils with triangular and inverted triangular profiles was designed, and the Green-Ampt model was employed for the process simulation. The results indicate that(1) the wetting front in coarse texture soils transports faster than in fine texture soils;(2) for the homogeneous case, the wetting front in triangularshaped soils transports faster than the inverted triangular type, but the triangular-shaped soils show a lower infiltration rate;(3) in the initial step, the wetting front in triangular-shaped soils shows higher transport speed, but depicts lower speed with increase in the time;(4) both the wetting front and infiltration rate show a significant exponential relation with the time. From these findings, an empirical model was developed which agrees well with the observed data and provides a useful method for this field of soil research.

关键词： Purple soil Triangular profile Inverted triangular profiles Soil water infiltration Empirical modeling

左心疾病相关肺动脉高压患者血钠水平与住院时间的相关性研究

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中国全科医学 2025年第9期28卷 1065-1071页

作者：孙琳施熠炜侯晓敏郭耘廷赵旭董霖聂继盛秦小江山西医科大学公共卫生学院山西医科大学第一医院山西医科大学基础医学院

背景左心疾病相关肺动脉高压（PH-LHD）是肺动脉高压（PH）中较常见的一种。研究表明，血钠水平与1类PH的严重程度和不良预后相关，然而，其对PH-LHD的影响鲜有报道。目的探讨PH-LHD患者的血钠水平与N末端脑利钠肽前体（NT-proBNP）、... 详细信息

背景左心疾病相关肺动脉高压（PH-LHD）是肺动脉高压（PH）中较常见的一种。研究表明，血钠水平与1类PH的严重程度和不良预后相关，然而，其对PH-LHD的影响鲜有报道。目的探讨PH-LHD患者的血钠水平与N末端脑利钠肽前体（NT-proBNP）、超声心动图指标的关系，评价血钠水平对PH-LHD严重程度及住院时间的影响，为PH-LHD患者的临床诊疗及提高医院周转率提供理论依据。方法回顾性收集2020年1月—2022年2月在山西医科大学第一医院住院的360例PH-LHD患者的临床资料，依据患者的中位血钠水平139 mmol/L（血钠<135 mmol/L为低血钠）将患者分为3组：血钠<135 mmol/L组（50例）、血钠135～139 mmol/L组（136例）、血钠140～145 mmol/L组（174例）。采用Spearman秩相关分析探讨血钠水平与住院时间、NT-proBNP及超声心动图指标的相关性；采用Kaplan-Meier生存曲线分析比较不同血钠水平PH-LHD患者的住院时间；采用二元Logistic回归分析探讨血钠水平对PH-LHD患者住院时间的影响。结果 3组PH-LHD患者年龄、住院时间、NT-proBNP、左心房前后径、右心房面积、左心室射血分数、缩短分数比较，差异有统计学意义（P<0.05）；其中血钠140～145 mmol/L组患者的住院时间、NT-proBNP低于血钠<135 mmol/L组及血钠135～139 mmol/L组（P<0.05）。Spearman秩相关分析结果显示，PH-LHD患者血钠水平与住院时间（rs=-0.176）、NT-proBNP(rs=-0.135)、右心室前后径（rs=-0.110）、肺动脉收缩压（rs=-0.105）均呈负相关（P<0.05）。Kaplan-Meier生存曲线分析结果显示，3组血钠水平的PH-LHD患者住院时间比较，差异有统计学意义（χ2=12.469,P=0.002）。二元Logistic回归分析校正各控制变量后结果显示，血钠水平升高是PH-LHD患者住院时间延长的保护因素（OR=0.916,95%CI=0.859～0.977,P=0.008）；与血钠140～145mmol/L患者相比，血钠<135 mmol/L(OR=2.268,95%CI=1.049～4.903,P=0.037)及血钠135～139 mmol/L(OR=2.056,95%CI=1.163～3.635,P=0.013)患者住院时间延长的风险均升高。结论血钠水平与PH-LHD严重程度密切相关，血钠水平降低是PH-LHD患者住院时间延长的独立危险因素，是一种潜在的治疗考虑因素，可为PH-LHD的诊疗及医院周转提供新策略。

关键词：肺动脉高压左心疾病相关肺动脉高压血钠超声心动图住院时间 Logistic模型

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Iridium(Ⅲ)-catalyzed two-fold C-H alkylation of BINOLs with allyl alcohols

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Organic Chemistry Frontiers 2022年第2期9卷 471-475页

作者： Hao Liu Wei Chi Meng-ling lin lin dong Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Sichuan Province Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial TechnologyWest China School of PharmacySichuan UniversityChengdu 610041China

Ir(Ⅲ)-Catalyzed C-H alkylation of BINOL units has been well examined by using allyl alcohols as coupling *** the advantage of the pyridine guiding group,the efficient protocol allows the rapid synthesis of diverse BI... 详细信息

关键词： alcohols allyl