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A new cosmological probe using super-massive black hole shadows

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Chinese Physics C 2020年第5期44卷 119-123页

作者： jing-zhao qi Xin Zhang Department of Physics College of SciencesNortheastern UniversityShenyang 110819China Ministry of Education’s Key Laboratory of Data Analytics and Optimization for Smart Industry Northeastern UniversityShenyang 110819China Center for High Energy Physics Peking UniversityBeijing 100080China Center for Gravitation and Cosmology Yangzhou UniversityYangzhou 225009China

We study the prospects of using the low-redshift and high-redshift black hole shadows as new cosmological standard rulers for measuring cosmological *** show that,using the low-redshift observation of the black hole shadow of M87?,the Hubble constant can be independently determined with a precision of about 13%as H0=70±9 km s?1 Mpc?*** high-redshift observations of super-massive black hole shadows may accurately determine a combination of parameters H0 andΩm,and we show by a simple simulation that combining them with the type Ia supernovae observations would give precise measurements of the cosmological parameters.

关键词： black hole shadow cosmological probe standard ruler cosmological parameters the Hubble constant

Transient acceleration in f(T) gravity

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Research in Astronomy and Astrophysics 2016年第2期16卷 13-18页

作者： jing-zhao qi Rong-Jia Yang Ming-Jian Zhang Wen-Biao Liu Department of Physics Institute of Theoretical Physics Beijing Normal University College of Physical Science and Technology Hebei University

Recently an f （T） gravity based on the modification of teleparallel gravity was proposed to ex-plain the accelerated expansion of the universe. We use observational data from type Ia supernovae, baryon acoustic oscillations, and cosmic microwave background to constrain this f（T） theory and reconstruct the effective equation of state and the deceleration parameter. We obtain the best-fit values of parameters and find an interesting result that the constrained f（T） theory allows for the accelerated Hubble expansion to be a transient effect.

关键词： f(T) gravity cosmology -- reconstruction -- observation

Study of deep transportation and plugging performance of deformable gel particles in porous media

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Petroleum Science 2024年第2期21卷 962-973页

作者： Wen-jing zhao jing Wang Zhong-Yang qi Hui-qing Liu National Key Laboratory of Petroleum Resources and Engineering China University of PetroleumBeijing102249China MOE Key Laboratory of Petroleum Engineering China University of PetroleumBeijing102249China

Deformable gel particles(DGPs) possess the capability of deep profile control and flooding. However, the deep migration behavior and plugging mechanism along their path remain unclear. Breakage, an inevitable phenomenon during particle migration, significantly impacts the deep plugging effect. Due to the complexity of the process, few studies have been conducted on this subject. In this paper, we conducted DGP flow experiments using a physical model of a multi-point sandpack under various injection rates and particle sizes. Particle size and concentration tests were performed at each measurement point to investigate the transportation behavior of particles in the deep part of the reservoir. The residual resistance coefficient and concentration changes along the porous media were combined to analyze the plugging performance of DGPs. Furthermore, the particle breakage along their path was revealed by analyzing the changes in particle size along the way. A mathematical model of breakage and concentration changes along the path was established. The results showed that the passage after breakage is a significant migration behavior of particles in porous media. The particles were reduced to less than half of their initial size at the front of the porous media. Breakage is an essential reason for the continuous decreases in particle concentration, size, and residual resistance coefficient. However, the particles can remain in porous media after breakage and play a significant role in deep plugging. Higher injection rates or larger particle sizes resulted in faster breakage along the injection direction, higher degrees of breakage, and faster decreases in residual resistance coefficient along the path. These conditions also led to a weaker deep plugging ability. Smaller particles were more evenly retained along the path, but more particles flowed out of the porous media, resulting in a poor deep plugging effect. The particle size is a function of particle size before inject

关键词： Physical simulation Deformable gel particle Breakage Particle size Residual resistance coefficient

What do parameterized Om(z) diagnostics tell us in light of recent observations?

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Research in Astronomy and Astrophysics 2018年第6期18卷 49-58页

作者： jing-zhao qi Shuo Cao Marek Biesiada Teng-Peng Xu Yan Wu Si-Xuan Zhang Zong-Hong Zhu Department of Astronomy Beijing Normal University Department of Astrophysics and Cosmology Institute of Physics University of Silesia

In this paper, we propose a new parametrization for Om(z) diagnostics and show how the most recent and significantly improved observations concerning the H(z) and SN Ia measurements can be used to probe the consistency or tension between the ΛCDM model and observations. Our results demonstrate that H0 plays a very important role in the consistency test of ΛCDM with H(z)data. Adopting the Hubble constant priors from Planck 2013 and Riess, one finds considerable tension between the current H(z) data and ΛCDM model and confirms the conclusions obtained previously by others. However, with the Hubble constant prior taken from WMAP9, the discrepancy between H(z) data and ΛCDM disappears, i.e., the current H(z) observations still support the cosmological constant scenario. This conclusion is also supported by the results derived from the Joint Lightcurve Analysis(JLA) SN Ia sample. The best-fit Hubble constant from the combination of H(z)+JLA(H00 = 68.81+1.5-1.49 km s-1 Mpc-1) is very consistent with results derived both by Planck 2013 and WMAP9, but is significantly different from the recent local measurement by Riess.

关键词： cosmology: theory cosmology: observations cosmology: cosmological parameters

Understanding the spatial interaction of ultrasounds based on three-dimensional dual-frequency ultrasonic field numerical simulation

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China Foundry 2024年第1期21卷 29-43页

作者： zhao-yang Yin qi-chi Le Yan-chao Jiang Da-zhi zhao qi-yu Liao qi Zou Key Lab of Electromagnetic Processing of Materials Ministry of EducationNortheastern UniversityShenyang 110819China School of Materials Science and Engineering Northeastern UniversityShenyang 110819China

A transient 3D model was established to investigate the effect of spatial interaction of ultrasounds on the dual-frequency ultrasonic field in magnesium alloy *** effects of insertion depth and tip shape of the ultrasonic rods,input pressures and their ratio on the acoustic field distribution were discussed in ***,the spacing,angle,and insertion depth of two ultrasonic rods significantly affect the interaction between distinct *** a result,various acoustic pressure distributions and cavitation regions are *** spherical rods mitigate the longitudinal and transversal attenuation of acoustic pressure and expand the cavitation volume by 53.7%and 31.7%,respectively,compared to the plate and conical *** the input pressure will enlarge the cavitation region but has no effect on the acoustic pressure distribution *** acoustic pressure ratio significantly affects the pressure distribution and the cavitation region,and the best cavitation effect is obtained at the ratio of 2:1(P15:P20).

关键词： dual-frequency ultrasonic numerical model acoustic pressure spatial interaction magnesium alloy

Latest insights into the global epidemiological features,screening,early diagnosis and prognosis prediction of esophageal squamous cell carcinoma

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World Journal of Gastroenterology 2024年第20期30卷 2638-2656页

作者： Yi-Xin zhao He-Ping zhao Meng-Yao zhao Yan Yu Xi qi Ji-Han Wang jing Lv Department of Clinical Laboratory Honghui HospitalXi’an Jiaotong UniversityXi’an 710054Shaanxi ProvinceChina Institute of Medical Research Northwestern Polytechnical UniversityXi’an 710072Shaanxi ProvinceChina

As a highly invasive carcinoma,esophageal cancer(EC)was the eighth most prevalent malignancy and the sixth leading cause of cancer-related death worldwide in *** squamous cell carcinoma(ESCC)is the major histological subtype of EC,and its incidence and mortality rates are decreasing *** to the lack of specific early symptoms,ESCC patients are usually diagnosed with advanced-stage disease with a poor prognosis,and the incidence and mortality rates are still high in many countries,especially in ***,enormous challenges still exist in the management of ESCC,and novel strategies are urgently needed to further decrease the incidence and mortality rates of *** the key molecular mechanisms underlying ESCC pathogenesis have not been fully elucidated,certain promising biomarkers are being investigated to facilitate clinical *** the advent and advancement of highthroughput technologies,such as genomics,proteomics and metabolomics,valuable biomarkers with high sensitivity,specificity and stability could be identified for ***,we aimed to determine the epidemiological features of ESCC in different regions of the world,especially in China,and focused on novel molecular biomarkers associated with ESCC screening,early diagnosis and prognosis prediction.

关键词： Esophageal squamous cell carcinoma Epidemiology Diagnosis Genomics Proteomics Metabolomics

New pimarane diterpenoids with antibacterial activity from fungus Arthrinium ***03

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Chinese Journal of Natural Medicines 2024年第4期22卷 356-364页

作者： zhao Songfeng jing Ziwei Department of Pharmacy the First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052China

A comprehensive chemical study of the endophytic fungus Arthrinium sp. ZS03, associated with Acorus tatarinowii Schott, yielded eleven pimarane diterpenoids (compounds 1–11), including seven novel compounds designated arthrinoids A–G (1–7). The determination of their structures and absolute configurations was achieved through extensive spectroscopic techniques, quantum chemical calculations of electronic circular dichroism (ECD), and single-crystal X-ray diffraction analysis. Furthermore, 7 demonstrated inhibitory activity against Klebsiella pneumoniae, comparable to the reference antibiotic amikacin, with a minimum inhibitory concentration (MIC) of 8 μg·mL^(−1).

关键词： Arthrinium sp.ZS03 Pimarane diterpenoids Structural elucidation Antibacterial activity

The Strategic Analysis of Demand Forecast-Sharing in a Hybrid-Format Online Platform Supply Chain

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Journal of Systems Science and Systems Engineering 2024年第3期33卷 281-310页

作者： jing zhao Zijun Yin Guobiao Zhou School of Mathematical Sciences Tiangong UniversityTianjin300387China

This paper examines the optimal forecast-sharing strategy in a hybrid-format online platform supply chain where a supplier sells a product through agency format and reselling format provided by a platform retailer who possesses demand forecasts from two *** asymmetry and co-opetitive relationship arise between the platform retailer and the supplier,which affect their operational decisions and the supply chain’s *** improve supply chain efficiency,we compare different forecast-sharing strategies(i.e.,no forecast sharing,sharing a single forecast,and sharing two forecasts),and analyze the effects of co-opetitive parameters on the optimal forecast-sharing *** analysis shows that forecast sharing is always beneficial to the supplier,and sharing two forecasts is more beneficial than sharing a single *** for the platform retailer and the whole supply chain,forecast sharing is beneficial only under certain conditions,depending on the co-opetitive *** optimal forecast-sharing strategy is the result of a combination of the negative effect of double marginalization in reselling channel and the positive effect of responding pricing to demand uncertainty in agency *** illustrate the parameter regions of the platform retailer’s voluntary sharing,contract sharing,and no sharing,and also find that higher channel competition intensity,higher market share of agency channel,and higher commission rate can promote the platform retailer’s voluntary *** study extends the research scope of demand forecast-sharing and sheds light on the decision-making processes for managing a hybrid-format online platform supply chain.

关键词： Supply chain management hybrid-format online platform demand forecast-sharing co-opetitive relationship channel competition intensity

Visible-light-driven photocatalysis degradation of antibiotic pollutants by La-doped CeO_(2) nanorods:synergy of La doping and oxygen vacancy

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Rare Metals 2024年第7期43卷 3134-3145页

作者： Shi-Hai Cao jing-Ru Qu Yu-qi zhao Yun-Tong Sun Wen-Tong Gao Bing Han Yao Lu College of Environmental Engineering Nanjing Institute of TechnologyNanjing 211167China School of Materials Science and Engineering Nanjing Institute of TechnologyNanjing 211167China School of Chemistry Chemical Engineering and BiotechnologyNanyang Technological UniversitySingapore 637459Singapore Institute of Environmental Health and Ecological Security School of Environment and Safety EngineeringJiangsu UniversityZhenjiang 212013China Jiangsu Collaborative Innovation Center of Technology and Material of Water Treatment Suzhou University of Science and TechnologySuzhou215009China

Elemental doping is an effective strategy to enhance photocatalytic activity and extend the light absorption range of single-component *** this work,a series of La-doped CeO_(2) nanorods(La-CeO_(2)-x) with La content of 1 wt%-15 wt% are synthesized by a simple hydrothermal method and further used as photocatalyst for sulfamerazine(SMR) *** prepared La-CeO_(2)-x nanorods exhibit a great improvement in electron-hole pair migration and visible-light response due to the synergistic effect of abundant oxygen vacancies and heterogeneous elements(La).Consequently,La-CeO_(2)-x exhibited excellent visible-light photocatalytic performances and chemical stability for SMR degradation,the La-CeO_(2)-5 sample achieved the highest SMR degradation rate of 81%,which was 3.4 times higher than that of the original CeO_(2).Furthermore,three possible degradation pathways of SMR in La-CeO_(2) photocatalytic reactions were proposed by liquid chromatography-mass spectrometry ***,density functional theory calculations were carried out to provide an in-depth understanding of the structure-performance *** its excellent properties and better photocatalytic performance,this study demonstrates that La doping in CeO_(2) is an effective way to increase oxygen vacancy and improve the photochemical properties of photocatalysts.

关键词： CeO_(2)nanorod La-doped Photocatalysis Oxygen vacancy Sulfamerazine