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A correction method for aero-optics thermal radiation effects based on gradient distribution and dark channel

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Optoelectronics Letters 2019年第5期15卷 374-380页

作者： hong han-yu SHI yu ZhanG Tian-xu LIU Zhao Hubei Key Laboratory of Optical Information and Pattern Recognition Hubei Research Centre of Video Image and High Definition Projection School of Electrical and Information Engineering Wuhan Institute of Technology Wuhan 430074 China National Key Laboratory of Science and Technology on Multi-Spectral Information Processing School of Automation Huazhong University of Science and Technology Wuhan 430074 China

In this paper, a new algorithm is proposed to remove the effects of aerodynamic optical thermal radiation from a single infrared image. In this method, the joint probability model of gradient distribution is introduced by studying the "global smoothing and local fluctuation" characteristics of the bias field. A prior L0 norm of dark channel is introduced to constrain the latent clear image. Finally, the split Bregman method is used to solve the optimization problem. The effectiveness of the proposed method is verified by a series of experiments, and the results are compared with the results of the existing methods for the correction of thermal radiation effects.

关键词： aero-optics thermal radiation effects gradient distribution dark channel

改性胶粉与水泥复合稳定建筑垃圾半刚性基层材料路用性能研究

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公路 2024年第8期69卷 87-93页

作者：姚明蔡东波韩洪宇柴少强姜海刚李金辉郑文华中交一公局第七工程有限公司郑州市451452 北京交通大学土木建筑工程学院北京市100044 北京建筑大学土木与交通工程学院北京市100044

为改善水泥稳定建筑垃圾半刚性基层材料路用性能,利用混凝土类建筑垃圾再生骨料替代不同比例的半刚性基层集料,基于抗裂型级配设计6种胶粉与水泥复合稳定建筑垃圾基层材料(再生骨料掺量0、30%、100%,原样及改性胶粉),测试混合料的力学... 详细信息

为改善水泥稳定建筑垃圾半刚性基层材料路用性能,利用混凝土类建筑垃圾再生骨料替代不同比例的半刚性基层集料,基于抗裂型级配设计6种胶粉与水泥复合稳定建筑垃圾基层材料(再生骨料掺量0、30%、100%,原样及改性胶粉),测试混合料的力学性能、抗裂性能及抗冻性能。发现改性胶粉与水泥复合稳定建筑垃圾再生骨料基层材料的力学性能指标随着再生骨料掺量的增加而降低,主要是由于建筑垃圾再生骨料内部存在微裂纹,其表面附着的水泥砂浆强度较低,造成界面薄弱区易发生破坏,对混合料的无侧限抗压强度及抗压回弹模量损伤较大。胶粉活化提高了其亲水性,增强了胶粉与再生骨料表面附着的水泥砂浆的黏结强度,提高了半刚性基层材料的抗开裂性能和抗冻性能。

关键词：道路工程半刚性基层碎石混合料建筑垃圾再生骨料改性胶粉路用性能

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某院碳青霉烯类抗菌药物的合理用药分析

抗感染药学 2024年第1期21卷 48-51页

作者：韩红玉陈耀升张英杰段晓颖河南中医药大学第一附属医院郑州450000 郑州市第二人民医院郑州450000

目的:分析医院碳青霉烯类抗菌药物的合理用药情况,为促进临床碳青霉烯类药物的合理使用提供参考。方法:选取2022年7月—12月郑州市第二人民医院住院患者的碳青霉烯类药物医嘱作为研究资料,采集患者的临床诊断、检查结果,以及所用碳青霉... 详细信息

目的:分析医院碳青霉烯类抗菌药物的合理用药情况,为促进临床碳青霉烯类药物的合理使用提供参考。方法:选取2022年7月—12月郑州市第二人民医院住院患者的碳青霉烯类药物医嘱作为研究资料,采集患者的临床诊断、检查结果,以及所用碳青霉烯类药物的品种、用法用量、疗程、联用药物等信息,依据《碳青霉烯类抗菌药物临床应用评价细则》对碳青霉烯类药物医嘱进行合理用药评价并进行分析。结果:2022年7月—12月医院共有84例次患者使用了碳青霉烯类药物,其涉及的临床科室主要有重症医学科(33例次,占39.29%)、呼吸与危重症医学科(12例次,占14.29%)和消化内科二(10例次,占11.90%);合理用药点评结果显示,84例次患者中共发现41条不合理用药情况,其中主要为适应证不适宜(16条,占39.02%)和用药前未进行病原学送检(14条,占34.15%)。结论:当前医院住院患者碳青霉烯类抗菌药物的使用仍存在较多的不合理现象,管理部门应当加强对临床的培训和管理,以提高其合理用药水平,最终保障患者用药的安全和有效。

关键词：碳青霉烯类药物抗菌药物合理用药医嘱点评

Phosphine-catalyzed acyl-transfer of heteroaryl ketones for the construction of N-fused heterocycles

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Chinese Chemical Letters 2024年第3期35卷 252-256页

作者： yu Zhang De-Rui han Dan Ye hong Lu Hao Wei Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education College of Chemistry&Materials ScienceNorthwest UniversityXi'an 710069China

An inexpensive phosphine catalyst was used effectively for a transition-metal-free acyl-transfer of N-containing heteroaryl ketones for the rapid synthesis of N-fused *** key pre-aromatic spirocyclic intermediate initialized by the single electron transfer(SET)process of Togni's reagentⅡpromoted by the tertiary phosphine resulted in an intriguing and alternative tactic for the cleavage of C–C *** using inexpensive tertiary phosphine as the catalyst,this skeleton-reorganizing approach of N-containing heteroaryl ketones allows a streamlined assembly of complex N-fused heterocycles with broad functional group tolerance.

关键词： Phosphine catalysis Acyl-transfer N-Fused heterocycles C–C bond activation Aromatization

Study on Active Oxygen Quantum Yield,Insecticidal Activities and Stability of Diphenylthiophene

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Agricultural Sciences in China 2007年第4期6卷 458-465页

作者： CHEN Xiao-jun XU han-hong WANG yu-jian HU Shan ZhanG Zhi-xiang ZhanG Yao-mou Key Laboratory of Pesticide and Chemical Biology Ministry of Education/Laboratory of Insect Toxicology South China Agricultural University Guangzhou 510642 P.R.China

Active oxygen quantum yield, insecticidal activities and stability of diphenylthiophene were studied for the first time. The results showed that maximum diphenylthiophene absorbency variety was 0.438 after irradiation for 280 min and that of α- terthienyl （α-T） was 0.480 after irradiation for 200 min with UV. LCs0 values ofdiphenylthiophene and α-T against 3rd instar larvae ofAedes albopictus were 9.18 × 10^-3 and 9.69× 10^-4 μg mL^-1 when treated for 24 h, respectively. LC50 values of the two chemicals against the 3rd instar larvae of Plutella xylostella were 267.87 and 222.22 μg mL^-1 when treated for 24 h, respectively. The half lives of diphenylthiophene and α-T in methanol were 113.62 and 10.65 h. Difference between quantum yield of diphenylthiophene and α-T was not significant and they all possessed high toxicity to Aedes albopictus and Plutella xylostella, but diphenylthiophene was more stable than α-T. It could be concluded that diphenylthiophene has overcome the deficiency of photoactivated insecticides which degraded quickly in the environment and could not be applied on the field. Diphenylthiophene could kill the insects and accelerate the degradation rate of triazophos. The benefits of diphenylthiophene can be further exploited and applied on the field.

关键词： diphenylthiophene insecticidal activities photocatalysis degradation

Corrosion behavior of pure metals(Ni and Ti)and alloys(316H SS and GH3535)in liquid GaInSn

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Nuclear Science and Techniques 2024年第3期35卷 70-83页

作者： Jian-Hui yu hong-Xia Xu Xiang-Xi Ye Bin Leng han-Xun Qiu Xing-Tai Zhou School of Materials and Chemistry University of Shanghai for Science and TechnologyShanghai 200093China Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China

In this study,the interactions between a Ga-based liquid metal,GaInSn,and several metal materials,including pure metals(Ni and Ti)and alloys(316H stainless steel(SS)and GH3535),at 650℃were *** aim was to evaluate the corrosion performance and select a suitable candidate material for use as a molten salt manometer diaphragm in thermal energy storage *** results indicated that the alloys(316H SS and GH3535)exhibited less corrosion than pure metals(Ni and Ti)in liquid ***-rich binary intermetallic compounds were found to form on the surfaces of all the tested metal materials exposed to liquid GaInSn,as a result of the decomposition of liquid GaInSn and its reaction with the constituent elements of the metal *** corrosion mechanism for all the tested materials exposed to liquid GaInSn was also investigated and proposed,which may aid in selecting the optimal candidate material when liquid GaInSn is used as the pressure-sensing medium.

关键词： Metal materials Liquid GaInSn Corrosion Intermetallic compounds Thermal energy storage systems

Sobolev Mapping of the Bergman Projections on Generalized Hartogs Triangles

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Acta Mathematica Sinica,English Series 2024年第2期40卷 451-466页

作者： hong Yan LIU Zhen han TU School of Mathematics and Statistics Wuhan UniversityWuhan 430072P.R.China

In this paper,we investigate Sobolev mapping properties of the Bergman *** domain we focus on is defined byΩm/n:={(z,w)∈C^(1+N):|w1|<|z|m1/n1<1,…|wN|<|z|/m_(N)/n_(N)<1},where m=(m1,…mN)∈(Z^(+))^(N),n=(n1,…nN)∈(Z^(+))N,N∈Z^(+).Sobolev irregularity of the Bergman projections on 2 is *** also prove some Sobolev regularity results of the Bergman projections onΩm/n for m=(1,…1).

关键词： Bergman projections generalized Hartogs triangles Sobolev spaces

Implications for fault reactivation and seismicity induced by hydraulic fracturing

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Petroleum Science 2024年第2期21卷 1081-1098页

作者： Zi-han Sun Ming-Guang Che Li-hong Zhu Shu-Juan Zhang Ji-yuan Lu Chang-yu Jin Key Laboratory of Ministry of Education on Safe Mining of Deep Metal Mines School of Resources and Civil Engineering and Key Laboratory of Liaoning Province on Deep Engineering and Intelligent TechnologyNortheastern UniversityShenyang110819LiaoningChina Research Institute of Petroleum Exploration&Development PetroChina Company LimitedBeijing100084China The Exploration and Development Research Institute of Daqing Oilfield Limited Company Daqing163458HeilongjiangChina

Evaluating the physical mechanisms that link hydraulic fracturing(HF) operations to induced earthquakes and the anticipated form of the resulting events is significant in informing subsurface fluid injection operations. Current understanding supports the overriding role of the effective stress magnitude in triggering earthquakes, while the impact of change rate of effective stress has not been systematically addressed. In this work, a modified critical stiffness was brought up to investigate the likelihood, impact,and mitigation of induced seismicity during and after hydraulic fracturing by developing a poroelastic model based on rate-and-state fraction law and linear stability analysis. In the new criterion, the change rate of effective stress was considered a key variable to explore the evolution of this criterion and hence the likelihood of instability slip of fault. A coupled fluid flow-deformation model was used to represent the entire hydraulic fracturing process in COMSOL Multiphysics. The possibility of triggering an earthquake throughout the entire hydraulic fracturing process, from fracturing to cessation, was investigated considering different fault locations, orientations, and positions along the fault. The competition between the effects of the magnitude and change rate of effective stress was notable at each fracturing stage. The effective stress magnitude is a significant controlling factor during fracturing events, with the change rate dominating when fracturing is suddenly started or stopped. Instability dominates when the magnitude of the effective stress increases(constant injection at each fracturing stage) and the change rate of effective stress decreases(the injection process is suddenly stopped). Fracturing with a high injection rate, a fault adjacent to the hydraulic fracturing location and the position of the junction between the reservoir and fault are important to reduce the Coulomb failure stress(CFS) and enhance the critical stiffness as

关键词： Hydraulic fracturing Coulomb failure stress Rate-and-state fraction model Linear stability analysis Critical stiffness Seismically induced fault

Enhanced corrosion resistance of epoxy resin coating via addition of CeO_(2) and benzotriazole

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Chinese Journal of Chemical Engineering 2024年第3期67卷 89-96页

作者： Xu han Ruijie Guo Baolong Niu hong Yan College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan 030024China Key Laboratory of Interface Science and Engineering in Advanced Materials Ministry of EducationTaiyuan University of TechnologyTaiyuan 030024China

The use of fillers to enhance the corrosion protection of epoxy resins has been widely *** this work,cerium dioxide(CeO_(2))and benzotriazole(BTA)were introduced into an epoxy resin to enhance the corrosion resistance of Q235 carbon *** electron microscopy results indicated that the CeO_(2) grains were rod-like and ellipsoidal in shape,and the distribution pattern of BTA was analyzed by energy dispersive *** dynamic potential polarization curve proved the excellent corrosion resistance of the composite epoxy resin with CeO_(2) and BTA co-addition,and electrochemical impedance spectroscopy test analysis indicated the significantly enhanced long-term corrosion protection performance of the composite *** the optimal protective performance was provided by the coating containing 0.3%(mass)CeO_(2) and 20%(mass)BTA,which was attributed to the barrier performance of CeO_(2) particles and the chemical barrier effect of *** formation of corrosion products was analyzed using X-ray *** addition,the corrosion resistance mechanism of the coating was also discussed in detail.

关键词： Benzotriazole Cerium dioxide Corrosion resistance Carbon steel Epoxy resin coating Preparation