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Controlling effects of differential swelling index on evolution of coal permeability

Journal of Rock Mechanics and Geotechnical Engineering 2020年第3期12卷 461-472页

作者： Chuanzhong Jiang Zhenfeng zhao xiwei Zhang Jishan Liu Derek Elsworth Guanglei Cui Key Laboratory of Ministry of Education on Safe Mining of Deep Metal Mines Northeastern UniversityShenyang110819China Beijing Key Laboratory for Precise Mining of Intergrown Energy and Resources China University of Mining and TechnologyBeijing100083China Oil&Gas Technology Research Institute Changqing Oilfield CompanyXi’an710018China Department of Chemical Engineering School of EngineeringThe University of Western Australia35 Stirling HighwayCrawleyWA6009Australia Department of Energy and Mineral Engineering G3 Centre and Energy InstituteThe Pennsylvania State UniversityUniversity ParkPA16802USA

Coal permeability measurements are normally conducted under the assumption that gas pressure in the matrix is equalized with that in fracture and that gas sorption-induced swelling/shrinking strain is uniformly distributed within the ***,the validity of this assumption has long been questioned and differential strain between the fracture strain and the bulk strain has long been considered as the primary reason for the inconsistency between experimental data and poroelasticity *** efforts have been made to incorporate the impact into coal permeability models,the fundamental nature of those efforts to split the matrix strain between fracture and coal bulk remains *** this study,a new concept of differential swelling index(DSI)was derived to theoretically define the relation among sorption-induced strains of the coal bulk,fracture,and coal matrix at the equilibrium *** was a function of the equilibrium pressure and its magnitudes were regulated by the Langmuir constants of both the matrix and the coal ***,a spectrum of DSI-based coal permeability models was developed to explicitly consider the effect of differential *** models were verified with the experimental data under the conditions of uniaxial strain,constant confining pressure,and constant effective stress.

关键词： Coal permeability Differential swelling behavior Gas adsorption Equilibrium pressure

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Cenozoic Denudation and Vertical Faulting History of the Central Segment of the Longmenshan Thrust Belt

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Acta Geologica Sinica(English Edition) 2016年第4期90卷 1541-1542页

作者： TAN Xibin XU xiwei LEE Yuanhsi KANG Wenjun zhao Shiliang Key Laboratory of Active Fault and Volcano Institute of GeologyChina Earthquake Administration Department of Earth and Environmental Sciences National Chung-Cheng University

Objective The uplift process and uplift mechanism of the Tibetan Plateau has been a research focus among geologists in recent years. This work put emphasis on the Cenozoic exhumation histories of the blocks bounded by the major faults at the central segment of the Longmenshan thrust belt, and the vertical faulting history, including the starting time and the total vertical displacement, of the major faults. Then we quantitatively established a complete active process for the central segment of the Longmenshan thrust belt, combining with the previous geophysical data in the deep and geologcial data. This study is critical for deeply and completely understanding the Cenozoic uplift history of the Longmenshan, and also provides thermochronology constraints to the different models for the uplift of the eastern margin of the Tibetan Plateau.

关键词： Cenozoic Denudation and Vertical Faulting History of the Central Segment of the Longmenshan Thrust Belt

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The kinetic study of light alkene syntheses by CO_(2) hydrogenation over Fe-Ni catalysts

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Frontiers of Chemical Science and Engineering 2010年第2期4卷 153-162页

作者： Yaling zhao Li WANG xiwei HAO Jiazhou WU Department of Chemical Engineering Xi'an Jiaotong UniversityXi'an 710049China

A kinetics model of CO_(2) hydrogenation over iron-nickel catalysts was developed based on the detailed mechanism of alkenes re-adsorption and secondary *** corresponding kinetical experiments are conducted in a continuous fixed bed *** effect of reaction conditions on catalyst performance was analyzed according to the results of orthogonal *** results of the experiments show that more methane in products can be obtained with iron-nickel catalysts,the trend of which is consistent with the thermodynamic ***,the content of alkenes in products is equivalent with that of *** shows that the reaction is controlled by *** all,the results of the experiments also substantiate that the model can give a good representation of the reaction mechanism of CO_(2) hydrogenation over iron-nickel *** parameters of this model give a better explanation for the question why the iron-nickel catalysts have a higher selectivity toward alkenes compared with other iron-based catalysts.

关键词： carbon dioxide hydrogenation light alkenes reaction mechanism kinetics model

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Prediction and evaluation method of TVB-N values distribution in pork by hyperspectral imaging

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International Journal of Agricultural and Biological Engineering 2021年第4期14卷 270-276页

作者： Yuweiyi Tang xiwei Wang Xiaoyang Xing Zhong Li Maocheng zhao College of Mechanical and Electronic Engineering Nanjing Forestry UniversityNanjing 210037China National Engineering Research Center of Biomaterials Nanjing Forestry UniversityNanjing 210037China Taizhou University Taizhou 225300JiangsuChina

Hyperspectral imaging makes it possible to map the spatial distribution of quality-indicating attributes over biological ***,inconsistencies may arise between these newly available qualitymaps of the same piece of the biological target from different chemometric ***,such inconsistency of the spatial prediction of the freshness-indicating attribute of total volatile basic nitrogen(TVB-N)over pork loins(Longissimus dorsi)was investigated in this work from the perspective of the accuracy and variation of pixel-wise prediction over the *** partial least square regression(PLSR)-based chemometric modelling was performed on the characteristic spectra of a target extracted from regions-of-interest(ROIs)of both the whole meat and the lean part only,after spectral preprocessing and spatial filtering,and coupled with waveband selection using successive projections algorithm(SPA).Results showed that all PLSR models achieved good and stable predictions of the average TVB-N values of pork loins,despite the differences of data-preprocessing or numbers of wavebands,with R2p being in the range from 0.832 to 0.889 for Meat-ROI and an even higher range from 0.846 to 0.912 if using Lean-ROIs,even with a reduced number of wavebands,accuracy remaining high in the range of R2p from 0.722 to 0.889 for Meat-ROIs and from 0.704 to 0.900 for *** contrast,however,devastating differences emerged between the predicted TVB-N distributions over a *** showed that excessive variation of pixel-wise predictions rendered utterly useless distribution maps resulted from a direct application of the PLSR or PLSR_SPA models from Meat or Lean ROIs,quantified by root-mean-error(RMSE)of pixel-wise predictions over 21.6 mg/100 g with PLSR,or even the worse with PLSR-SPA,shooting absurdly high about 55 mg/100 *** appropriate spatial filtering,the excessive between-pixel variation was suppressed to below 8.5 mg/100 g in RMSE,presenting visually be

关键词： pork TVB-N hyperspectral imaging prediction evaluation distribution PLSR SPA

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参与调控细胞程序性死亡蛋白1及其配体1信号通路的研究进展

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中华临床医师杂志（电子版） 2020年第2期14卷 149-153页

作者：贾玲玲张文凯刘凯赵希伟刘倩侯林义山西医科大学第二医院心胸外科太原030001 山西医科大学第二医院重症医学科太原030001

细胞程序性死亡蛋白1及其配体1(PD-1/PD-L1)通路已经成为研究热点,无论在抗肿瘤还是在抗炎方面均取得了一定的成果,但具体的机制目前尚不完全清楚。本文介绍了PD-1及PD-L1的分子结构、功能以及与其他通路之间的关系。PD-1蛋白是免疫抑... 详细信息

细胞程序性死亡蛋白1及其配体1(PD-1/PD-L1)通路已经成为研究热点,无论在抗肿瘤还是在抗炎方面均取得了一定的成果,但具体的机制目前尚不完全清楚。本文介绍了PD-1及PD-L1的分子结构、功能以及与其他通路之间的关系。PD-1蛋白是免疫抑制分子,与其配体PD-L1结合起促进细胞凋亡的作用。在肿瘤或炎症中,JAK/STAT、NF-κB、MAPK、PI3K以及TIM-3/Gal-9等其他信号通路被激活,诱导免疫细胞及肿瘤细胞高表达PD-1及PD-L1,使免疫细胞活性降低,消耗增加,募集减少,从而使机体抗肿瘤、抗炎能力下降。PD-1/PD-L1与JAK/STAT、NF-κB、MAPK、PI3K以及TIM-3/Gal-9等其他信号通路也起相互调控作用。PD-1/PD-L1抑制剂与JAK/STAT、NF-κB、MAPK、PI3K以及TIM-3/Gal-9等通路抑制剂联合应用,在抗肿瘤以及肿瘤耐药性方面取得了突破性进展。然而,相对于PD-1/PD-L1对肿瘤作用的研究而言,PD-1/PD-L1在炎症方面的研究相对较少,无相应的药物应用于临床,需要大量的基础研究支持。

关键词：细胞程序性死亡蛋白1及其配体1 抑制剂肿瘤,免疫治疗抗炎治疗信号通路

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Distribution and risk factor analysis for-associated diarrhea among hospitalized children over one year of age

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Pediatric Investigation 2020年第1期4卷 37-42页

作者： Chunna zhao Shu Guo Xiaoyun Jia xiwei Xu Department of Gastroenterology Beijing Children's HospitalFaculty of Digestive DiseasesCapital Medical UniversityNational Clinical Research Center for Digestive DiseasesBeijing 100045China

Importance: Clostridium difficile-associated diarrhea (CDAD) is a severe type of antibiotic-associated diarrhea (AAD). However, the risk factors for CDAD in children with AAD have not yet been ***: To investigate the distribution and risk factors for CDAD among hospitalized children in Beijing Children’s ***: Stool samples from 197 children with AAD were tested for theC. difficile pathogenic genes (tcdA, tcdB, tcdC, tcdD, tcdE, cdtA, andcdtB) using polymerase chain reaction between January 2011 and January 2014. Children who tested positive fortcdA ortcdB were included in the CDAD group, and those remaining comprised the non-CDAD ***: The rate of CDAD among the 197 children with AAD was 42.6% (84/197). The age distribution was 1-15.6 years, among which the majority of children (54.8%, 46/84) were aged 1-4 years. Differences in the CDAD-positive rates among AAD children belonging to different age groups were not statistically significant. Univariate analysis revealed that the duration of antibiotic therapy, the length of hospitalization prior to diarrhea, and gastrointestinal tract operations were significant risk factors (P < 0.05). Children with CDAD underwent more antibiotic therapy and had longer periods of hospitalization prior to diarrhea onset than children in the non-CDAD group. Using multivariate regression analysis, hospitalization for ≥ 10 days prior to diarrhea was found to be an independent risk factor for ***: This study revealed that the length of hospitalization (≥ 10 days) prior to diarrhea was an independent risk factor for CDAD in children with AAD.

关键词： Antibiotics Children Clostridium difficile Diarrhea

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High-performance γ-MnO_(2) Dual-Core,Pair-Hole Fiber for Ultrafast Photonics

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Ultrafast Science 2023年第1期3卷 19-25页

作者： Xiaohui Li Xiangzhen Huang Yueheng Han Enci Chen Penglai Guo Wenmin Zhang Mingqi An Zhiwen Pan Qian Xu Xiaoxiao Guo xiwei Huang Yishan Wang Wei zhao School of Physics and Information Technology Shaanxi Normal UniversityXian 710000ShaanxiChina School of Electronic Engineering Guangxi University of Science and TechnologyLiuzhou 545006GuangxiChina Schoolof Computer Science and Engineering Macao University of Science and TechnologyTaipa 999078MacaoChina State Key Laboratory of Transient Optics and Photonics Xi'an Institute of Optics and Precision MechanicsChinese Academy of SciencesXi'an 710119ShaanxiChina

Manganese dioxide(MnO2)is a widely used and well-studied 3-dimensional(3D)transition metal oxide,which has advantages in ultrafast optics due to large specific surface area,narrow bandgap,multiple pores,superior electron transfer capability,and a wide range of light ***,few studies have considered its excellent performance in ultrafast photonics.y-MnO2 photonics devices were fabricated based on a special dual-core,pair-hole fiber(DCPHF)carrier and applied in ultrafast optics fields for the first *** results show that the soliton molecule with tunable temporal separation(1.84 to 2.7 ps)and 600-MHz harmonic solitons are achieved in the *** result proves that this kind of photonics device has goodapplications in ultrafast lasers,high-performance sensors,fiber optical communications,etc.,which can help expand the prospect of combining 3D materials with novel fiber for ultrafast optics device technology.

关键词： fiber optics performance

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Microstructure, Mechanical Properties, Corrosion Behavior and Biocompatibility of As-Extruded Biodegradable Mg–3Sn–1Zn–0.5Mn Alloy

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Journal of Materials Science & Technology 2016年第9期32卷 874-882页

作者： Lida Hou Zhen Li Hong zhao Yu Pan Sergey Pavlinich xiwei Liu Xinlin Li Yufeng Zheng Li Li Center for Biomedical Materials and Engineering Harbin Engineering UniversityHarbin 150001China Institute of Materials Processing and Intelligent Manufacturing Harbin Engineering UniversityHarbin 150001China Hospital of Heilongjiang Province Harbin 150001China Department of Materials Science and Engineering College of EngineeringPeking UniversityBeijing 100871China

The microstructure evolution and mechanical properties of biodegradable Mg-3Sn-1Zn-0.5Mn alloys were investigated by the optical microscopy, X-ray diffractometer and a universal material testing machine. The corrosion and degradation behaviors were studied by potentiodynamic polarization method and immersion test in a simulated body fluid （SBF）. It was found that the as-extruded Mg-3Sn-1Zn-0.5Mn alloy has the fine equiaxed grains which underwent complete dynamic recrystallization during the hot extrusion process, with the second phase particles of Mg2Sn precipitated on the grain boundaries and inside the grains. The tensile strength and elongation of as-extruded Mg-3Sn-1Zn-0.5Mn alloys were 244 ± 3.7 MPa and 19.3% ± 1.7%, respectively. The potentiodynamic polarization curves in SBF solution indicated the better corrosion resistance of the as-extruded Mg-3Sn-1Zn-0.5Mn alloy in the SBF solution. Immersion test in the SBF solution for 720 h revealed that the corrosion rate of as-extruded Mg-3Sn-1Zn-0.5Mn alloy was nearly 4±0.33 ram/year. The hemolysis rate of as-extruded Mg-3Sn-1Zn-0.5Mn alloy was lower than the safe value of 5% according to ISO 10993-4. As-extruded Mg-3Sn- 1Zn-0.5Mn alloy showed good biocompatibility after being implanted into the dorsal muscle and the femoral shaft of the rabbit, and no abnormalities were found after short-term implantation. It was revealed that the as-extruded Mg-3Sn-1Zn-0.5Mn alloy is a promising material for biodegradable implants, which possesses an interesting combination of preferred mechanical properties, better corrosion resistance and biocompatibility.

关键词： Biodegradable magnesium alloy Extrusion Mechanical property Corrosion Biocompatibility

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Cyber-physical-social System in Intelligent Transportation

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IEEE/CAA Journal of Automatica Sinica 2015年第3期2卷 320-333页

作者： Gang Xiong Fenghua Zhu xiwei Liu Xisong Dong Wuling Huang Songhang Chen Kai zhao the State Key Laboratory of Management and Control for Complex Systems Institute of AutomationChinese Academy of Science the Cloud Computing Center Chinese Academy of Sciences Qingdao Academy of Intelligent Industries Beijing Engineering Research Center for Intelligent Systems and Technology Institute of AutomationChinese Academy of Science

A cyber-physical system(CPS) is composed of a physical system and its corresponding cyber systems that are tightly fused at all scales and *** is helpful to improve the controllability,efficiency and reliability of a physical system,such as vehicle collision avoidance and zero-net energy buildings *** has become a hot R&D and practical area from US to EU and other *** fact,most of physical systems and their cyber systems are designed,built and used by human beings in the social and natural ***,social systems must be of the same importance as their *** indivisible cyber,physical and social parts constitute the cyber-physical-social system(CPSS),a typical complex system and it’s a challengeable problem to control and manage it under traditional theories and *** artificial systems,computational experiments and parallel execution(ACP) methodology is introduced based on which data-driven models are applied to social *** systems,i.e.,cyber systems,are applied for the equivalent description of physical-social system(PSS).Computational experiments are applied for control plan *** parallel execution finally realizes the stepwise control and management of ***,a CPSS-based intelligent transportation system(ITS) is discussed as a case study,and its architecture,three parts,and application are described in detail.

关键词： Cyber-physical-social system(CPSS) ACP approach intelligent transportation system(ITS) parallel control and management internet of vehicles social transportation network

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基于粒子群优化算法BP神经网络的2型糖尿病危险因素分析及筛查模型构建

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华西医学 2024年第2期39卷 251-258页

作者：王仕鸿陈永泽麦振华谭茜蔚杨子华王爽赵乐马勇黄翠怡孔丹莉丁元林于海兵广东医科大学公共卫生学院广东东莞523808

目的基于粒子群优化算法(particle swarm optimization, PSO)BP神经网络,分析2型糖尿病的危险因素,并构建2型糖尿病筛查模型。方法选择2021年7月-2022年8月广东医科大学附属医院和广东医科大学附属第二医院内分泌科2型糖尿病住院患者... 详细信息

目的基于粒子群优化算法(particle swarm optimization, PSO)BP神经网络,分析2型糖尿病的危险因素,并构建2型糖尿病筛查模型。方法选择2021年7月-2022年8月广东医科大学附属医院和广东医科大学附属第二医院内分泌科2型糖尿病住院患者为病例组,以同期广东医科大学附属医院健康管理中心的健康体检人群为对照组。收集研究对象的基本信息、体检资料和实验室检查指标等进行比较分析。运用MATLAB R2021b软件分别构建PSO-BP神经网络模型、BP神经网络模型和logistic回归模型,并选出最优的2型糖尿病筛查模型。在此基础上,采用平均影响值算法筛选2型糖尿病发病的危险因素。结果病例组共纳入患者1 053例,对照组共纳入健康体检人群914例。除食盐类型、共病家族史、体质量指数、总胆固醇、低密度脂蛋白胆固醇、主食摄入外(P>0.05),其余指标两组比较,差异均有统计学意义(P<0.05)。PSO-BP神经网络模型的整体筛查性能优于BP神经网络模型和logistic回归模型。基于PSO-BP神经网络模型,平均影响值算法因素筛选结果显示2型糖尿病发病的危险因素为空腹血糖、心率、年龄、腰臂比和婚姻状况,保护因素为高密度脂蛋白胆固醇、蔬菜摄入、居住地、文化程度、水果摄入和肉类摄入。结论 2型糖尿病的影响因素较多,应重点关注高危人群并定期开展疾病筛查,减少2型糖尿病的发病风险。PSO-BP神经网络筛查模型的性能最佳,未来可推广至其他疾病的早期筛查及诊断。

关键词： 2型糖尿病粒子群优化算法 BP神经网络平均影响值算法危险因素

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