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Creep-Resistant Covalent Adaptable Networks with Excellent SelfHealing and Reprocessing Performance via Phase-Locked Dynamic Covalent Benzopyrazole-Urea Bonds

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Chinese Journal of Polymer Science 2024年第10期42卷 1545-1556,I0013页

作者： miao xie Xiao-Rong Wang Zhan-Hua Wang He-Sheng Xia State Key Laboratory of Polymer Materials Engineering Polymer Research InstituteSichuan UniversityChengdu610065China School of Petrochemical Engineering Liaoning Petrochemical UniversityFushun113001China

Covalent adaptive networks(CANs)are capable of undergoing segment rearrangement after being heated,which endows the materials with excellent self-healing and reprocessing performance,providing an efficient solution to the environment pollution caused by the plastic *** main challenge remains in developing CANs with both excellent reprocessing performance and creep-resistance *** this study,a series of CANs containing dynamic covalent benzopyrazole-urea bonds were developed based on the addition reaction between benzopyrazole and isocyanate *** calculation confirmed that relatively low dissociation energy is obtained through undergoing a five-member ring transition state,confirming excellent dynamic property of the benzopyrazole-urea *** verified by the FTIR results,this nice dynamic property can be well maintained after incorporating the benzopyrazole-urea bonds into polymer *** self-healing and reprocessing performance is observed by the 3-ABP/PDMS elastomers owing to the dynamic benzopyrazole-urea *** separation induced by the aggregation of the hard segments locked the benzopyrazole-urea bonds,which also makes the elastomers display excellent creep-resistance *** hard phase locking strategy provides an efficient approach to design CANs materials with both excellent reprocessing and creep-resistance performance.

关键词： Covalent adaptive networks Self-healing polymer Dynamic covalent bond

Numerical Simulation of Coal Floor Fault Activation Influenced by Mining

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Journal of China University of Mining and Technology 2006年第4期16卷 385-388页

作者： WANG Lian-guo miao xie-xing School of Sciences China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

By means of the numerical simulation software ANSYS, the activation regularity of coal floor faults caused by mining is simulated. The results indicate that the variation in horizontal, vertical and shear stresses, as well as the horizontal and vertical displacements in the upper and the lower fault blocks at the workface are almost identical. Influ- enced by mining of the floor rock, there are stress releasing and stress rising areas at the upper part and at the footwall of the fault. The distribution of stress is influenced by the fault so that the stress isolines are staggered by the fault face and the stress is focused on the rock seam around the two ends of the fault. But the influence in fault activation on the upper or the lower fault blocks of the workface is markedly different. When the workface is on the footwall of the fault, there is a horizontal tension stress area on the upper part of the fault; when the workface is on the upper part of the fault, it has a horizontal compressive stress area on the lower fault block. When the workface is at the lower fault block, the maximum vertical displacement is 5 times larger then when the workface is on the upper fault block, which greatly in- creases the chance of a fatal inrush of water from the coal floor.

关键词： mining fault activation: simulation

Numerical Analysis of Finite Deformation of Overbroken Rock Mass in Gob Area Based on Euler Model of Control Volume

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Journal of China University of Mining and Technology 2006年第3期16卷 245-248页

作者： LIU Wei-qun miao xie-xing School of Sciences China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

The overbroken rock mass of gob areas is made up of broken and accumulated rock blocks compressed to some extent by the overlying strata. The beating pressure of the gob can directly affect the safety of mining fields, formarion of road retained along the next goaf and seepage of water and methane through the gob. In this paper, the software RFPA＇2000 is used to construct numerical models. Especially the Euler method of control volume is proposed to solve the simulation difficulty arising from plastically finite deformations. The results show that three characteristic regions occurred in the gob area：（1） a naturally accumulated region, 0-10 m away from unbroken surrounding rock walls, where the beating pressure is nearly zero; （2） an overcompacted region, 10-20 m away from unbroken walls, where the beating pressure results in the maximum value of the gob area; （3） a stable compaction region, more than 20 m away from unbroken walls and occupying absolutely most of the gob area, where the beating pressures show basically no differences. Such a characteristic can exolain the easy-seeoaged “O”-ring phenomena around mining fields very well.

关键词： overbroken rock mass plastically finite deformation method of control volume bearing pressure

EGFR-targeted and gemcitabine-incorporated chemogene for combinatorial pancreatic cancer treatment

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Nano Research 2024年第2期17卷 848-857页

作者： miao xie Qiushuang Zhang Yuanyuan Guo Lijuan Zhu Xinyuan Zhu Chuan Zhang School of Chemistry and Chemical Engineering Frontiers Science Center for Transformative MoleculesInstitute of Molecular MedicineSixth people’s HospitalSchool of MedicineShanghai Key Laboratory for Molecular Engineering of Chiral DrugsShanghai Jiao Tong UniversityShanghai 200240China Department of Radiology Shanghai Jiao Tong University Affiliated Sixth People’s HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghai 200233China Institute of Molecular Medicine Shanghai Jiao Tong University Affiliated Renji HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghai 200127China

Pancreatic cancer stands out as a recognized intractable tumor due to its high malignancy and mortality rates,which are largely attributed to the insensitivity of current clinical chemotherapies or *** chemo and gene therapy that integrates different therapeutic targets,may increase the chemosensitivity of pancreatic cancer and synergistically enhance the antitumor ***,conventional co-delivery of gene and chemo drugs is intensively dependent on complex nanoparticle delivery systems,thus would be limited by unstable drug packaging,nonspecific biodistribution,and biosafety ***,we rationally designed an epidermal growth factor-receptor(EGFR)-targeted and gemcitabine-incorporated oligonucleotide(termed as chemogene)with anti-Bcl-2 sequence,which achieves simple and precise integration of gemcitabine into a gene regulative agent,as well as the EGFR-targeted delivery for pancreatic cancer *** solid-phase synthesis,gemcitabine,as the first-line chemodrug for pancreatic cancer,is introduced to the antisense oligonucleotide to replace all cytosine nucleosides to obtain the gemcitabine-integrated chemogene(Ge-ASO^(Bcl-2)).Thereafter,Ge-ASO^(Bcl-2)is covalently coupled with EGFR nanobody to construct the final targeted chemogene without any exogenous ***,this nanobody-conjugated chemogene exhibits remarkable tumor targeting capability and antitumor effects both in vitro and in vivo,which initiates a first step toward the application of combinatorial chemo and gene therapy for future pancreatic cancer treatment.

关键词： antisense oligonucleotide chemogene nanobody drug delivery system pancreatic cancer

Magnetic resonance imaging features of intrahepatic extramedullary hematopoiesis: Three case reports

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World Journal of Clinical Cases 2022年第19期10卷 6626-6635页

作者： Ma Luo Jia-Wen Chen Chuan-miao xie Department of Radiology Sun Yat-sen University Cancer CenterGuangzhou 510060Guangdong ProvinceChina State Key Laboratory of Oncology in South China Guangzhou 510060Guangdong ProvinceChina Collaborative Innovation Center for Cancer Medicine Guangzhou 510060Guangdong ProvinceChina

BACKGROUND Extramedullary hematopoiesis rarely occurs within the liver alone,and is easily *** radiological literature on this disease is exclusively case *** is a paucity of literature on the role of magnetic resonance imaging(MRI).The most common imaging modalities used are computed tomography and *** report aims to provide more data on the appearance of extramedullary hematopoiesis using MRI to help radiologists establish the *** SUMMARY Three patients(one male and two females)were incidentally found to have a hepatic mass or nodule,without hepatomegaly or *** tests including liver function,serum hepatic tumor markers,and hepatitis serologic markers were *** MRI scans,all lesions showed lower signal intensity on in-phase images than on out-phase *** case showed changes in signal intensity on T2 weighted images(WI)and diffusion WI,which shifted from hyperintensity to hypointensity with size enlargement between two rounds of imaging *** lesions exhibited different enhancement patterns on dynamic contrast enhancement *** The MRI signal change and in-/out-phase image might provide useful information and help radiologists establish the diagnosis of intrahepatic extramedullary hematopoiesis.

关键词： Liver Extramedullary hematopoiesis Signal intensity Magnetic resonance imaging Case report

Bifurcation and catastrophe of seepage flow system in broken rock

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Mining Science and Technology 2009年第1期19卷 1-7页

作者： miao xie-xing LI Shun-cai CHEN Zhan-qing School of Sciences China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China School of Mechanical and Electrical Engineering Xuzhou Normal University Xuzhou Jiangsu 221116 China

The study of dynamical behavior of water or gas flows in broken rock is a basic research topic among a series of key projects about stability control of the surrounding rocks in mines and the prevention of some disasters such as water inrush or gas outburst and the protection of the groundwater resource. It is of great theoretical and engineering importance in respect of promo- tion of security in mine production and sustainable development of the coal industry. According to the non-Darcy property of seepage flow in broken rock dynamic equations of non-Darcy and non-steady flows in broken rock are established. By dimensionless transformation, the solution diagram of steady-states satisfying the given boundary conditions is obtained. By numerical analysis of low relaxation iteration, the dynamic responses corresponding to the different flow parameters have been obtained. The stability analysis of the steady-states indicate that a saddle-node bifurcaton exists in the seepage flow system of broken rock. Consequently, using catastrophe theory, the fold catastrophe model of seepage flow instability has been obtained. As a result, the bifurcation curves of the seepage flow systems with different control parameters are presented and the standard potential function is also given with respect to the generalized state variable for the fold catastrophe of a dynamic system of seepage flow in broken rock.

关键词： broken rock non-Darcy flow stability saddle-node bifurcation fold catastrophe

Waste-filling in fully-mechanized coal mining and its application

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Journal of China University of Mining and Technology 2008年第4期18卷 479-482页

作者： miao xie-xing ZHANG Ji-xiong FENG Mei-mei State Key Laboratory for Geomechanics ＆ Deep Underground Engineering China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China School of Sciences China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China School of Mines China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

A fully-mechanized coal mining (FMCM) technology capable of filling up the goaf with wastes (including solid wastes) is described. Industrial tests have proved that by using this technology not only can waste be re-used but also coal resources can be exploited with a higher recovery rate without removing buildings located over the working faces. Two special devices, a hydraulic support and a scraper conveyor, run side-by-side on the same working face to simultaneously realize mining and filling. These are described in detail. The tests allow analysis of rock pressure and ground subsidence when backfilling techniques are employed. These values are compared to those from mining without using backfilling techniques, under the same geological conditions. The concept of equivalent mining height is proposed based on theoretical analysis of rock pressure and ground subsidence. The upper limits of the rock pressure and ground subsidence can be estimated in backfilling mining using this concept along with traditional engineering formulae.

关键词： fully-mechanized coal mining coal mining with gangue backfilling mining under buildings railways and water bodies rock pressure around coal face control of ground subsidence

Experimental Study into Permeability of Broken Mudstone

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Journal of China University of Mining and Technology 2007年第2期17卷 147-151页

作者： MA Zhan-guo miao xie-xing ZHANG Fan LIYu-shou School of Sciences China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

Much attention should be paid to the permeability of broken rocks in goafs for the sake of water preservation in mining and to prevent disasters. Using a special device together with the MTS815.02 Rock Mechanics Test System,we tested the permeability of broken mudstone during its compacting process,and obtained the relations between axial stress and differential seepage pressure and between the pressure gradient and the seepage velocity. The effect of axial stress,grain size,and seepage velocities on the permeability coefficient is analyzed. The results show that 1) permability varies abruptly when the load reaches the compressive strength of rock samples,2) for a constant seepage velocity,the differential seepage pressure and the axial stress can be expressed by an exponential function,3) for a constant axial stress,the pressure gradient and the seepage velocity can be also expressed by an exponential function and 4) the permeability coefficient of broken mudstone of different sizes is closely related to its compaction state and will decrease with the increase of axial stress,expressed as a logarithmic function.

关键词： rock mechanics broken mudstone axial stress seepage properties test

Effect of ground stress on hydraulic fracturing of methane well

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Journal of China University of Mining and Technology 2008年第2期18卷 204-209页

作者： DU Chun-zhi MAO Xian-biao miao xie-xing WANG Peng School of Sciences China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

Most of the coal reservoirs in China are of low-permeability, so hydraulic fracturing is widely used to improve the per- meability in the extraction of gas by ground drilling. The ground stress around the well was analyzed by using theory of elasticity. The pressure when the well fractured is formulated and the effect of ground stress on pressure is discussed. The effect of ground-stress-differences on hydraulic fracturing was analyzed by using the numerical software RFPA2D-Flow in reference to the tectonic stress in Jincheng coal area. The results show that: 1) the position where initial fracture appears is random and fracture branches emerge when the fractures expand if ground stresses in any two directions within a horizontal plane are equal; 2) other- wise, the fractures expand in general along the direction of maximum ground stress and the critical pressure decreases with in- creasing ground-stress-differences and 3) the preferred well-disposition pattern is diamond shaped. The preferred well spacing is 250 m×300 m. This study can provide a reference for the design of wells.

关键词： ground stress hydraulic fracturing breakdown pressure RFPA^2D-Flow design of wells