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Empirical equations between characteristic impedance and mechanical properties of rocks

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Journal of Rock Mechanics and Geotechnical Engineering 2020年第5期12卷 975-983页

作者： Zong-xian zhang De-Feng Hou Adeyemi Aladejare Oulu Mining School University of OuluOulu90014Finland College of Resources and Safety Engineering China University of Mining and TechnologyBeijing100083China

Based on a great number of experimental data on various mechanical properties of rock in the literature,six empirical equations between the characteristic impedance(product of density and P-wave velocity)and mechanical properties of rock are *** properties include uniaxial compressive strength,tensile strength,shear strength,mode I fracture toughness,Young’s modulus,and Poisson’s *** empirical equations show that the values of the aforementioned properties increase with increase in characteristic *** also implies that the characteristic impedance of rock may be considered as an index to represent the main properties of *** this sense,it is possible to consider using characteristic impedance to classify rock masses for studies in the future.

关键词： Characteristic impedance Mechanical properties Rock mass Classification Strength

Biomacromolecular nanostructures-based interfacial engineering: from precise assembly to precision biosensing

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National Science Review 2018年第5期5卷 740-755页

作者： fan Yang Xiaolei Zuo Chunhai fan xian-En zhang Division of Physical Biology & Bioimaging Center Shanghai Synchrotron Radiation FacilityShanghai Institute of Applied PhysicsChinese Academy of Sciences National Key Laboratory of Biomacromolecules CAS Excellence Center for BiomacromoleculesInstitute of BiophysicsChinese Academy of Sciences School of Laboratory Medicine Hubei University of Chinese Medicine

Biosensors are a type of important biodevice that integrate biological recognition elements, such as enzyme,antibody and DNA, and physical or chemical transducers, which have revolutionized clinical diagnosis especially under the context of point-of-care tests. Since the performance of a biosensor depends largely on the bio–solid interface, design and engineering of the interface play a pivotal role in developing quality biosensors. Along this line, a number of strategies have been developed to improve the homogeneity of the interface or the precision in regulating the interactions between biomolecules and the interface. Especially,intense efforts have been devoted to controlling the surface chemistry, orientation of immobilization,molecular conformation and packing density of surface-confined biomolecular probes(proteins and nucleic acids). By finely tuning these surface properties, through either gene manipulation or self-assembly, one may reduce the heterogeneity of self-assembled monolayers, increase the accessibility of target molecules and decrease the binding energy barrier to realize high sensitivity and specificity. In this review, we summarize recent progress in interfacial engineering of biosensors with particular focus on the use of protein and DNA nanostructures. These biomacromolecular nanostructures with atomistic precision lead to highly regulated interfacial assemblies at the nanoscale. We further describe the potential use of the high-performance biosensors for precision diagnostics.

关键词： biosensor interface engineering homogeneity orientation control fused proteins DNA nanostructures

Test research on sticking mechanism during hot rolling of SUS 430 ferritic stainless steel

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International Journal of Minerals,Metallurgy and Materials 2010年第5期17卷 573-578页

作者： Jun-xian Liu Yong-jun zhang Jing-tao Han School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

The sticking phenomenon during hot rolling of SUS 430 ferritic stainless steel was investigated by means of a two-disc type high-temperature wear tester. The test results indicate that sticking particles on the surfaces of high chromium steel （HiCr） and high-speed steel （HSS） rolls undergo nucleation, growth, and saturation stages. Grooves on the roll surface generated by grinding provide nucleation sites for sticking particles. The number of sticking particles on the HiCr roll surface is greater than that on the HSS roll surface. The average surface roughnesses （Ra） of HiCr and HSS rolls change from 0.502 and 0.493 μm at the initial stage to 0.837 and 0.530 μm at the saturation stage, respectively. The test further proves that the sticking behavior is strongly dependent on roll materials, and the HSS roll is more benefi- cial to prevent particles sticking compared with the HiCr roll under the same hot-rolling conditions.

关键词： ferritic steel stainless steel hot rolling sticking rolls

Time-variant reliability analysis of a continuous system with strength deterioration based on subset simulation

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Advances in Manufacturing 2019年第2期7卷 188-198页

作者： Xi-Nong En Yi-Min zhang xian-Zhen Huang School of Mechanical Engineering and Automation Northeastern University Shenyang 110819 People's Republic of China Equipment Reliability Institute Shenyang University of Chemical Technology Shenyang 110142 People's Republic of China

To conduct a reliability analysis for mechanical components, it is necessary to consider the combined influence of strength deterioration and dynamic loads. An efficient method based on subset simulation is proposed in this paper to analyze time-variant reliability by considering the strength deterioration of mechanical components in a continuous system. A gamma process is used to describe the deterioration of system strength. A model for timevariant reliability considering strength deterioration is constructed for a continuous system. A representative example and tubular cantilever structure are assessed to demonstrate the efficiency and accuracy of the proposed method. The reliability probability examples were analyzed using a first-order reliability method and benchmark results for the proposed method were derived using direct Monte Carlo simulation (MCS). The results of the proposed method and MCS are consistent, indicating that the proposed method is an effective reliability analysis method for evaluating small failure probabilities in a continuous system subjected to strength deterioration and dynamic loads.

关键词： Time-variant reliability Strength deterioration Subset simulation (SS) Continuous system

An empirical approach for predicting burden velocities in rock blasting

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Journal of Rock Mechanics and Geotechnical Engineering 2021年第4期13卷 767-773页

作者： Zong-xian zhang Li-Yuan Chi Changping Yi Oulu Mining School University of OuluOuluFI-90014Finland State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijingChina Division of Mining and Geotechnical Engineering Lulea University of TechnologyLuleaSweden

An analytical relation between burden velocity and ratio of burden to blasthole diameter is developed in this *** relation is found to be consistent with the measured burden velocities of all 37 full-scale blasts found from published *** blasts include single-hole blasts,multi-hole blasts,and simultaneously-initiated blasts with various borehole diameters such as 64 mm,76 mm,92 mm,115 mm,142 mm and 310 *** boreholes were fully *** agreement between measured and calculated burden velocities demonstrates that this relation can be used to predict the burden velocity of a wide range of full-scale blast with fully-coupled explosive charge and help to determine a correct delay time between adjacent holes or rows in various full-scale blasts involved in tunnelling(or drifting),surface and underground mining production blasts and underground opening slot *** addition,this theoretical relation is found to agree with the measured burden velocities of 9 laboratory small-scale blasts to a certain *** predict the burden velocity of a small-scale blast,a further study or modification to the relation is necessary by using more small-scale blasts in the future.

关键词： Burden velocity Rock blasting Kinetic energy Delay time Tunnelling Minin

Interfacial engineering of metallic rhodium by thiol modification approach for ambient electrosynthesis of ammonia

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Nano Research 2022年第10期15卷 8826-8835页

作者： Meng Jin Xinyuan zhang xian zhang Hongjian Zhou Miaomiao Han Yunxia zhang Guozhong Wang Haimin zhang Laboratory of Materials Physics Centre for Environmental and Energy NanomaterialsAnhui Key Laboratory of Nanomaterials and NanotechnologyCAS Center for Excellence in NanoscienceInstitute of Solid State PhysicsHFIPSChinese Academy of SciencesHefei 230031China University of Science and Technology of China Hefei 230026China School of Science Huzhou UniversityHuzhou 313000China

Here we report a vapor-phase reaction approach to fabricate rhodium(I)-dodecanethiol complex coated on carbon fiber cloth(Rh(I)-SC_(12)H_(25)/CFC),followed by low-temperature pyrolysis to achieve dodecanethiol modified Rh(Rh@SC_(12)H_(2)5/CFC)for electrocatalytic nitrogen reduction reaction(NRR).The results demonstrate that after pyrolysis for 0.5 h at 150℃,the obtained Rh@SC_(12)H_(2)5/CFC-0.5 exhibits excellent NRR activity with an NH3 yield rate of 121.2±6.6μg∙h^(−1)∙cm^(−2)(or 137.7±7.5μg∙h^(−1)∙mgRh^(−1))and a faradaic efficiency(FE)of 51.6%±3.8%at−0.2 V(***)in 0.1 M Na_(2)SO_(4).The theoretical calculations unveil that the adsorption of dodecanethiol on the hollow sites of Rh(111)plane is thermodynamically favorable,effectively regulating the electronic structure and surface wettability of metallic ***,the dodecanethiol modification on Rh(111)obviously decreases the surface H*coverage,thus inhibiting the competitive hydrogen evolution reaction and concurrently reducing the electrocatalytic NRR energy barrier.

关键词： dodecanethiol modification electrocatalysis low temperature pyrolysis nitrogen reduction reaction surface H*coverage

Global trend of review articles focused on cardiopulmonary bypass:Perspectives from bibliometrics

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World Journal of Methodology 2025年第2期15卷 166-173页

作者： Lei Deng Rui Zhou xian-Jie zhang Yan-Hua Peng Department of Gastroenterology Deyang People’s HospitalDeyang 618000Sichuan ProvinceChina Department of Anesthesiology and Perioperative Medicine Shanghai Fourth People's HospitalSchool of MedicineTongji UniversityShanghai 200434China Department of Anesthesiology Deyang People’s HospitalDeyang 618000Sichuan ProvinceChina

BACKGROUND Cardiopulmonary bypass(CPB)is a life-support technology widely used in *** articles reflect research advances in a certain topic or field within a certain period of *** To perform a bibliometric analysis of the review articles that focused on CPB for cardiovascular *** This study was based on a bibliometric *** were acquired from the Web of Science and basic bibliometric parameters were analyzed and visualized using VOSviewer and *** We identified 141 review articles on ***,the number of publications increased,and most of them were published in the 2010s(n=57,40.4%)and the 2020s(n=45,31.9%).There were 113(80.1%)narrative review articles,21(14.9%)meta-analysis studies and 7(5.0%)systematic review *** United States(n=25,17.7%)and China(n=21,14.9%)were the leading countries in terms of publication *** articles were published in 98 different *** Journal of Cardiothoracic and Vascular Anesthesia(n=14,10.0%)and Perfusion-United Kingdom(n=11,7.8%)were preferred by the *** high-frequency keywords included inflammatory response,children,acute kidney injury,meta-analysis and off-pump,except for CPB and cardiac *** response had the closest relationship with CPB during cardiac *** complications of CPB,including inflammatory response,kidney injury and ischemia,caught lots of *** The rapid increase of review papers shows that the research on CPB in cardiac surgery is increasingly being emphasized by scholars and clinical staff ***-analysis has been widely conducted to analyze clinical controversies and further guide clinical *** to improving the outcomes of patients undergoing cardiac surgery with CPB are the hot spots in this field.

关键词： Cardiopulmonary bypass Review article Bibliometric analysis Cardiac surgery Hot spots

Theoretical Study on Vibrational Spectra, Detonation Properties and Pyrolysis Mechanism for Cyclic 2-Diazo-4,6-dinitrophenol

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Chinese Journal of Chemical Physics 2012年第5期25卷 545-551,I0003页

作者： Xiao-hong Li Geng-xin Yin xian-zhou zhang College of Physics and Engineering Henan University of Science and TechnologyLuoyang 471003China Luoyang Key Laboratory of Photoelectric Functional Materials Henan University of Science andTechnologyLuoyang 471023China College of Physics and Information Engineering Henan Normal UniversityXinxiang 453007China

Based on the full optimized molecular geometrical structures at the DFT-B3LYP/6- 311＋G^＊＊ level, there exists intramolecular hydrogen bond interaction for cyclic 2-diazo- 4,6-dinitrophenol. The assigned infrared spectrum is obtained and used to compute the thermodynamic properties. The results show that there are four main characteristic regions in the calculated IR spectra of the title compound. The detonation velocities and pressures are also evaluated by using Kamlet-Jacobs equations based on the calculated density and condensed phase heat of formation. Thermal stability and the pyrolysis mechanism of 2- diazo-4,6-dinitrophenol are investigated by calculating the bond dissociation energies at the B3LYP/6-311＋G^＊＊ level.

关键词： Cyclic 2-diazo-4 6-dinitrophenol Pyrolysis mechanism Detonation property Infrarecl spectrum

"Forever chemicals":a sticky environmental problem

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Frontiers of Environmental Science & Engineering 2024年第10期18卷 175-183页

作者： Junhua fang Shaolin Li Rongliang Qiu Wei-xian zhang College of Environmental Science and Engineering State Key Laboratory of Pollution Control and Resource ReuseTongji UniversityShanghai 200092China Guangdong Laboratory for Lingnan Modern Agriculture Guangzhou 510642China College of Natural Resources and Environment Guangdong Provincial Key Laboratory of Agricultural&Rural Pollution Abatement and Environmental SafetySouth China Agricultural UniversityGuangzhou 510642China

The discovery and widespread use of per-and poly-fluoroalkyl substances(PfaS)have exemplified the beneficial role of chemistry in modern life,yet *** also underscored significant environmental and health *** "forever chemicals"due to their remarkable persistence,PfaS present formidable challenges in terms of contamination and *** to address these challenges have led to the development of innovative degradation technologies,such as hydrothermal alkali treatment(HALT),low-temperature mineralization,and mechanochemical degradation,offering promising solutions to PfaS ***,these advancements must be accompanied by robust investment in research,collaboration among stakeholders,and global responsibility to ensure effective management of Pfas contamination and mitigate its adverse impacts on ecosystems and humanhealth.

关键词： PfaS Degradation technologies Environmental remediation Global responsibility