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Synthesis, Characterization and Biological Activities of Novel Water-soluble Metalloporphyrins

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Chinese Chemical Letters 2001年第12期12卷 1085-1088页

作者： Li, ZY Zhang, YN Gao, zt Liu, Y Zhu, XJ Wuhan Univ Dept Chem Wuhan 430072 Peoples R China

The synthesis, characterization, and biological activities of a series of metal porphyrins were described. The complexes 3a similar to 3e were prepared from the reaction of compound 2 with M(OAc)(2) in CHCl3, and the treatment of 3a similar to 3f with pyridine gave corresponding complexes 4a similar to 4f. These new compounds were identified by absorption spectroscopies, H-1 NMR and elemental analysis. The results of biological activity,testing revealed that 4a and 4c had stronger inhibiting action for Escherichia coli (CCTCC AB91115).

关键词： water-soluble metalloporphyrin synthesis structure characterization biological activity testing

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高温高含冰量冻结砂土的三轴压缩力学特性

哈尔滨工业大学学报 2024年第7期56卷 124-131页

作者：马付龙刘恩龙王丹康建宋丙堂冻土工程国家重点实验室(中国科学院西北生态环境资源研究院) 兰州730000 中国科学院大学北京100049 四川大学水利水电学院成都610065

为深入研究高温高含冰量冻土的力学特性与变形机制,以不同含冰量的冻结砂土为研究对象,通过开展-1.5℃下的三轴压缩试验,讨论了围压和含冰量对冻结砂土力学特性的影响,并分析了常规饱和冻土与高含冰量冻土在变形机制上的差异。结果表明... 详细信息

为深入研究高温高含冰量冻土的力学特性与变形机制,以不同含冰量的冻结砂土为研究对象,通过开展-1.5℃下的三轴压缩试验,讨论了围压和含冰量对冻结砂土力学特性的影响,并分析了常规饱和冻土与高含冰量冻土在变形机制上的差异。结果表明:针对砂土提出的“冰砂混合,分层压实,下部补水”的制样方法可制出土颗粒分布均匀的高含冰量饱和冻土试样;高含冰量冻结砂土与饱和冻结砂土的强度和体变差异很大,但不同含冰量的高含冰量冻结砂土的应力-应变关系和体变很接近;不同围压下的67%含冰质量分数冻结砂土均为应变软化型,且随着围压的增大,试样应变软化的程度逐渐降低,体变逐渐由体胀向体缩转化;饱和冻结砂土受力时是由土颗粒、冰和未冻水共同承担;而高含冰量冻结砂土主要由冰直接承担外力,冰中夹杂的土颗粒间接地影响了冰的力学性质。

关键词：高温高含冰量冻土砂土三轴试验力学特性变形机制

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黎曼流形上的粒子群运动模型

四川大学学报（自然科学版） 2024年第3期61卷 62-68页

作者：唐伦潇蔚涛罗懋康四川大学数学学院成都610064

自然界中生物群的协同运动模式多种多样,运动空间的复杂性对该多样性起着关键作用.为描述生物群的协调运动,人们基于欧氏空间提出了多种粒子群运动模型.然而,这些模型往往只能描述简单的运动模式.本文基于Morse势和黎曼流形提出了一个... 详细信息

自然界中生物群的协同运动模式多种多样,运动空间的复杂性对该多样性起着关键作用.为描述生物群的协调运动,人们基于欧氏空间提出了多种粒子群运动模型.然而,这些模型往往只能描述简单的运动模式.本文基于Morse势和黎曼流形提出了一个新模型,该模型可以描述任意运动空间中的群体运动,且易于工程实现.本文分别以球面、环面、Möbius带及类丘陵曲面为代表仿真分析了黎曼曲面的紧致性、亏格、可定向性及高斯曲率等性质对模型的影响.结果显示,紧致性导致粒子群聚合得更加紧密对称,非零亏格导致群体中粒子的运动速度趋于一致并阻止粒子群形成类涡流形态,不可定向性导致粒子群在任何条件下都趋于分散,而高斯曲率对粒子群运动行为的影响较小.此外,本文还研究了当曲面包含一个、两个及三个障碍物时模型的输出,结果显示,当势强度足够大时,粒子群能够趋向目标,也能包围目标或绕行障碍物.综上,相比已有模型,该模型能够描述更为丰富的运动模式.

关键词：粒子群协同运动黎曼流形迴避

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Knowledge and attitudes of orthopedic surgeons regarding prosthesis joint infection

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World Journal of Orthopedics 2023年第4期14卷 240-247页

作者： Mahmut Nedim Aytekin Imran Hasanoglu Recep Öztürk Nihat Tosun Department of Orthopedics and Traumatology Ankara Yıldırım Beyazıt UniversityFaculty of MedicineAnkara 06500Turkey Department of Infectious Diseases and Clinical Microbiology Ankara Yıldırım Beyazıt UniversityFaculty of MedicineAnkara City HospitalAnkara 06500Turkey Department of Orthopedics and Traumatology Dr.Abdurrahman Yurtaslan Ankara Oncology Training and Research HospitalAnkara 06200Turkey

BACKGROUND Periprosthetic joint infection(PJI)is a critical complication after joint arthroplasty and is accompanied by increasing rates of morbidity and *** studies have aimed at preventing *** To research the knowledge level and attitudes of orthopedic surgeons,who play a key role in both preventing and managing *** We conducted a web-based survey to evaluate orthopedic surgeons'knowledge level and attitudes regarding *** Likert scale survey utilized consisted of 30 questions which were prepared based on the"Proceedings of the International Consensus on Periprosthetic Joint Infection".RESULTS A total of 264 surgeons participated in the *** average age was 44.8,and 173 participants(65.5%)had more than 10 years of *** statistically significant relationship was found between the PJI knowledge of the surgeons and their years of ***,participants who worked in training and research hospitals demonstrated higher levels of knowledge than the ones in the state *** was also noticed that surgeons'knowledge concerning the duration of antibiotic therapy and urinary infections was not consistent with their *** Even though orthopedic surgeons have adequate knowledge about preventing and managing PJI,their attitudes might contradict their *** studies are required to examine the causes and solutions of the contradictions between orthopedic surgeons'knowledge and attitudes.

关键词： Antibiotic prophylaxis Periprosthetic joint infection Prevention Total joint replacement Turkey

Frictional sliding of infilled planar granite fracture under oscillating normal stress

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International Journal of Mining Science and Technology 2023年第6期33卷 687-701页

作者： kang Tao Wengang Dang Yingchun Li School of Civil Engineering Sun Yat-sen UniversityZhuhai 519086China State Key Laboratory of Coal Resources and Safe Mining China University of Mining and TechnologyXuzhou 221116China Southern Marine Science and Engineering Guangdong Laboratory Zhuhai 519086China State Key Laboratory of Coastal and Offshore Engineering Dalian University of TechnologyDalian 116024China

This paper investigates the frictional behavior of the infilled rock fracture under dynamic normal stress.A series of direct shear tests were conducted on saw-cut granite fractures infilled with quartz using a selfdeveloped dynamic shear apparatus,and the effects of normal load oscillation amplitude,normal load oscillation period and sliding velocity were *** test results reveal that the shear response can be divided into three stages over a whole loading-unloading process,characterized by different time spans and stress ***,a smaller oscillation amplitude,a longer oscillation period and a fast shear velocity promote the stability of the friction system,which is also confirmed by the Coulomb failure criterion calculated based on the observed periodic apparent friction *** dynamic strengthening/weakening phenomenon is dependent on the oscillation amplitude and product of sliding velocity and oscillation period(vT).Also,the rate and state friction law incorporating the parameter a that characterizes the normal stress variation is employed to describe the dynamic friction coefficient but exhibits an incompetent performance when handling intensive variation in normal ***,the potential seismicity induced by oscillating normal stress based on the observed stress drop is *** work helps us understand the sliding process and stability evolution of natural faults,and its benefits for relative hazard mitigation.

关键词： Granite fracture Quartz gouge Normal load oscillation Frictional stability Rate and state friction law

ZUR KENNTNISS DER GATTUNGEN BORNHARDTINA SCHULZ UND STRINGOCEPHALUS DEFR

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地质学报 1936年第3期 343-351+353-359+439-441页

作者： zt.MARBURG

Auf einer zusammen mit Herrn Professor Wedekind im M(a|¨)rz 1936ausgeführten Exkursion in die Eifel haben wir bei Niederehe und Ahütteim oberen Korallenkalk der Hillesheimer Mulde zahlreiche Exemplareglatter Uncite... 详细信息

关键词： der St Za In ZUR KENNTNISS DER GATTUNGEN BORNHARDTINA SCHULZ UND STRINGOCEPHALUS DEFR DER

A damage-coupled multi-axial time-dependent low cycle fatigue failure model for SS304 stainless steel at high temperature

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Acta Metallurgica Sinica(English Letters) 2011年第2期24卷 169-174页

作者： Yujie LIU Qing GAO Guozheng kang School of Mechanics and Engineering Southwest Jiaotong University Chengdu 610031 China

Based on the time-dependent strain cyclic characteristics and fatigue behaviors of SS304 stainless steel under multi-axial cyclic loading at 700 ？ C, and in the frame of unified visoco-plastic cyclic constitutive model and continuum damage mechanics theory, the damage-coupled multi-axial time-dependent constitutive model and fatigue failure model were proposed. In the model, the evolution equation of damage was introduced in and the time-dependent effects, e.g. holding time, loading rate, were taken into account. The model was applied to the simulation of whole-life cyclic deformation behaviors and prediction of LCF life for SS304 stainless steel in multiaxial time-dependent low cycle fatigue tests. It is shown that the simulated results agree well with experimental ones.

关键词： SS304 stainless steel Constitutive model Low cycle fatigue Failure model Damage-coupled High temperature

Solution of the finite slab criticality problem using an alternative phase function with the second kind of Chebyshev polynomials

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Nuclear Science and Techniques 2019年第2期30卷 135-141页

作者： Hakan ?ztürk ?kke? Ege Department of Physics Faculty of Arts and SciencesOsmaniye Korkut Ata University

The critical size of a finite homogenous slab is investigated for one-speed neutrons using the alternative phase function(AG, Anli-Gungor) in place of the scattering function of the transport equation. First of all, the neutron angular flux expanded in terms of the Chebyshev polynomials of second kind(UN approximation) together with the AG phase function is applied to the transport equation to obtain a criticality condition for the ***, using various values of the scattering parameters, the numerical results for the critical half-thickness of the slab are calculated and they are tabulated in the tables together with the ones obtained from the conventional spherical harmonic(PN) method for comparison. They can be said to be in good accordance with each other.

关键词： Criticality problem UN method Neutron transport equation Alternative phase function

Frictional behavior of planar and rough granite fractures subjected to normal load oscillations of different amplitudes

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Journal of Rock Mechanics and Geotechnical Engineering 2022年第3期14卷 746-756页

作者： Wengang Dang kang Tao Xinfan Chen School of Civil Engineering Sun Yat-sen UniversityZhuhai519082China State Key Laboratory of Coal Resources and Safe Mining China University of Mining and TechnologyXuzhou221116China Southern Marine Science and Engineering Guangdong Laboratory Zhuhai519082China

The dynamic frictional behaviors of natural discontinuities(joints,fractures,faults)play an important role in geohazards assessment;however,the mechanisms of the dynamic fault weakening/strengthening are still *** this paper,a dynamic shear box was used to perform direct shear tests on saw-cut(planar)and natural(rough)granite fractures,with different normal load oscillation *** on the recorded shear forces and normal displacements,the shear forces,apparent friction coefficients and normal displacements are found to change periodically with oscillated normal loads and are characterized by a series of time *** observed changing patterns are similar for the rough and planar *** with the test data under constant normal load(CNL),small/large normal load oscillation amplitude enhances/reduces the peak shear strength,with a critical *** magnitude of critical normal load oscillation for the rough fractures is smaller than the planer *** results imply that dynamic fault weakening/strengthening can be achieved by both normal load oscillation amplitudes and slip surface *** rough fractures with larger normal oscillation amplitude can easily cause frictional weakening under stress disturbance.

关键词： Direct shear test Normal load oscillation fracture roughness Critical oscillation amplitude Dynamic weakening/strengthening