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Petroleum Science 2021年第6期18卷 1760-1775页

作者： Dao-Yi Zhu zhi-Hua deng Si-Wei Chen State Key Laboratory of Petroleum Resources and Prospecting and Petroleum School China University of Petroleum-Beijing at KaramayKaramay834000XinjiangChina

Polymer gel systems have been widely applied to control excessive water and improve oil recovery(IOR)in petroleum *** are usually divided into two main types,in-situ cross-linked polymer gels,and pre-formed polymer *** recent years,nuclear magnetic resonance(NMR) technology has been gradually applied to the research of polymer gel systems due to its unique analysis *** paper is intent to review these works *** in-situ cross-linked polymer gel systems,NMR can be used to characterize the chemical structure changes of the polymer,the cross-linker,and the auxiliary agent in the formulation of the polymer gel ***,the gelation time and the gel strength of the in-situ cross-linked polymer gel systems can also be measured by *** pre-formed polymer gels,NMR can be employed to detect the chemical structure of the designed ***,the NMR method can evaluate the plugging,water control,and oil improvement performance of the polymer gels in porous media without using *** review can help readers build a more systematic understanding of the application of NMR technology in polymer gel systems for IOR and help re searchers to more deeply study the performance of polymer gel systems.

关键词： Nuclear magnetic resonance Polymer gels Gelation time Gel strength Conformance control

Surface metallization of PTFE and PTFE composites by ion implantation for low-background electronic substrates in rare-event detection experiments

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Nuclear Science and Techniques 2022年第7期33卷 37-47页

作者： Shao-Jun Zhang Yuan-Yuan Liu Sha-Sha Lv Jian-Ping cheng Bin Liao Pan Pang zhi deng Li He College of Nuclear Science and Technology Beijing Normal UniversityJoint Laboratory of Jinping Ultra-low Radiation Background Measurement of Ministry of Ecology and Environment Beijing Normal UniversityKey Laboratory of Beam Technology of Ministry of EducationBeijing Normal UniversityBeijing100875China Beijing Radiation Center Beijing100875China Department of Engineering Physics Key Laboratory of Particle and Radiation Imaging of Ministry of EducationTsinghua UniversityBeijing100084China Joint Research Center Nuctech Company LimitedBeijing100084China

Polytetrafluoroethylene(PTFE)is a low-background polymer that is applied to several applications in rare-event detection and underground low-background ***-based electronic substrates are important for reducing the detection limit of high-purity germanium detectors and scintillator calorimeters,which are widely applied in dark matter and 0υββdetection *** traditional adhesive bonding method between PTFE and copper is not conducive to working in liquid nitrogen and extremely low-temperature *** avoid adhesive bonding,PTFE must be processed for surface metallization owing to the mismatch between the PTFE and copper conductive ***-background PTFE matrix composites(m-PTFE)were selected to improve the electrical and mechanical properties of PTFE by introducing SiO_(2)/TiO_(2) *** microstructures,surface elements,and electrical properties of PTFE and m-PTFE were characterized and analyzed following ion *** and m-PTFE surfaces were found to be broken,degraded,and cross-linked by ion implantation,resulting in C=C conjugated double bonds,increased surface energy,and increased surface ***,the surface roughness,bond strength,and conjugated double bonds of m-PTFE were significantly more intense than those of ***,the interface bonding theory between PTFE and the metal copper foil was analyzed using the direct metallization ***,the peel strength of the optimized electronic substrates was higher than that of the industrial standard at extremely low temperatures,while maintaining excellent electrical properties.

关键词： Surface modification Polytetrafluoroethylene Ion implantation Surface metallization Low temperature resistance

Ursolic Acid Prevents Retinoic Acid-Induced Bone Loss in Rats

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Chinese Journal of Integrative Medicine 2019年第3期25卷 210-215页

作者： cheng Min LIANG Xu-hua WANG Qing-wei deng Ya-ting ZHAO zhi-xin LIU Xue-ying College of Biology Pharmacy and Food Engineering Shangluo University Department of Pharmacy The Second Affiliated Hospital Fourth Military Medical University Department of Pharmacology Xi'an Medical College Department of Medicinal Chemistry Fourth Military Medical University

Objective: To examine the effects of ursolic acid(UA) on mitigating retinoic acid(RA)-induced osteoporosis in rats. Methods: Fifty female Sprague-Dawley rats were randomly divided into the control group(n=10) and the osteoporosis group(n=40). The 40 osteoporosis rats were induced by 75 mg/(kg·d) RA once daily for 2 weeks, and then were randomly assigned to vehicle control(model), low-, middle-, and high-dose UA [(UA-L, UA-M, UA-H; 30, 60, 120 mg/(kg·d), respectively] groups(10 rats each). UA were administered once daily to the rats from the 3 rd weeks for up to 4 weeks by gavage. Bone turnover markers [serum alkaline phosphatase(ALP), osteocalcin(OCN), urine deoxypyridinoline(DPD)] and other parameters, including serum calcium(S-Ca), serum phosphorus(S-P), urine calcium(U-Ca), urine phosphorus(U-P), and bone mineral density(BMD) of the femur, 4 th lumbar vertebra and tibia, bone biomechanical properties and trabecular microarchitecture, were measured. Results: The osteoporosis in rats was successfully induced by RA. Compared with the model group, UA-M and UA-H significantly reversed the RA-induced changes in S-P, U-Ca, U-P, ALP, OCN and urine DPD ratio and markedly enhanced the BMD of right femur, 4 th lumbar vertebra and tibia(P<0.05 or P<0.01). Further, biomechanical test and microcomputed tomography evaluation also showed that UA-H drastically improved biomechanical properties and trabecular microarchitecture(P<0.05 or P<0.01). Conclusion: UA could promote bone formation, increase osteoblastic activity and reduce osteoclastic activity in rats, indicating that UA might be a potential therapeutic of RA-induced acute osteoporosis.

关键词： osteoporosis bone turnover ursolic acid bone mineral density biomechanics microcomputed tomography

Multi-resonator coupled metamaterials for broadband vibration suppression

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Applied Mathematics and Mechanics(English Edition) 2021年第1期42卷 53-64页

作者： Pengcheng ZHAO Kai ZHANG cheng ZHAO Zichen deng School of Mechanics Civil Engineering and ArchitectureNorthwestern Polytechnical UniversityXi’an 710072China MIIT Key Laboratory of Dynamics and Control of Complex Systems Northwestern Polytechnical UniversityXi’an 710072China

In this study,multi-resonator coupled metamaterials(MRCMs)with local resonators are proposed to obtain the multiple and wide band *** models of the MRCMs are established,and the boundary conditions of the unit cell are obtained with Bloch's *** effects of structural parameters,including the mass of the resonator and the spring stiffness,on the distributions of the band gaps are ***,the frequency domain responses and the time domain responses are calculated for analyzing the structural vibration characteristics and the effects of damping on structural *** results show that the frequency domain response can accurately express the distributions of the band gaps of the MRCMs,and we can increase the number and the width of the band gaps by using the MRCMs for the superior vibration suppression capability.

关键词： multi-resonator coupled metamaterial(MRCM) band gap broadband vibration suppression

Approach for analyzing the ultimate strength of concrete filled steel tubular arch bridges with stiffening girder

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第5期8卷 682-692页

作者： ZHANG zhi-cheng XIE Xu ZHANG He CHEN Heng-zhi Department of Civil Engineering Zhejiang University Hangzhou 310027 China

A convenient approach is proposed for analyzing the ultimate load carrying capacity of concrete filled steel tubular (CFST) arch bridge with stiffening girders. A fiber model beam element is specially used to simulate the stiffening girder and CFST arch rib. The geometric nonlinearity, material nonlinearity, influence of the construction process and the contribution of prestressing reinforcement are all taken into consideration. The accuracy of this method is validated by comparing its results with experimental results. Finally, the ultimate strength of an abnormal CFST arch bridge with stiffening girders is investigated and the effect of construction method is discussed. It is concluded that the construction process has little effect on the ultimate strength of the bridge.

关键词： Ultimate strength Concrete filled steel tubular (CFST) arch bridge Stiffening girder Fiber model beam element Construction process

Irregular Spatial Distributions of Spectral Line Parameters in the Middle Solar Chromosphere Revealed from Analysis of Solar Flash MgⅠb_(2)Spectra

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Research in Astronomy and Astrophysics 2022年第8期22卷 111-124页

作者： Yuhang Jin Zhongquan Qu zhi Xu Guangtao Dun Liang Chang Xiangming cheng Xiaoyu Zhang Linhua deng Yang Peng School of Astronomy and Space Science University of Chinese Academy SciencesBeijing 100049China Yunnan Observatories Chinese Academy of SciencesKunming 650216China

This paper presents the analytical results of solar MgⅠb_(2)flash spectra,obtained by the prototype Fiber Arrayed Solar Optic Telescope in process of the 2013 Gabon total solar *** analysis reveals irregular distributions of the spectral line parameters like ratio of line source function to continuum oneβ,ratio of line emissivity to continuum emissivityζ,ratio of the continuum opacity to the line opacity r_(0),line center optical depthτ_(0)、,the line widthΔλ_(D),and the line-of-sight velocity v_(los),while the approximately spherical symmetry can be found in the maps of integrated line intensity and continuum *** irregular distributions originate from those of line profile features like the maximum intensity,the line width and line center *** is also found from the recovered line center optical depthτ_(0) that in the middle chromosphere,the optical depth is not small due to nonignorable absorption and the long light path along the ***,we show that the excessive broadening of spectral lines can be due to co-existence of multiple radiative sources with different line-of-sight velocities unresolved in one detector pixel.

关键词： Sun:atmosphere Sun:chromosphere Sun:fundamental parameters

Role of estrogen receptor β selective agonist in ameliorating portal hypertension in rats with CCl4-induced liver cirrhosis

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World Journal of Gastroenterology 2016年第18期22卷 4484-4500页

作者： cheng-Gang Zhang Bin Zhang Wen-Sheng deng Ming Duan Wei Chen zhi-Yong Wu Department of Gastrointestinal Surgery Ren Ji Hospital School of Medicine Shanghai Jiao Tong University Department of General Surgery Yueyang Hospital of Integrated Traditional Chinese and Western Medicine Shanghai University of Traditional Chinese Medicine

AIM: To investigate the role of diarylpropionitrile(DPN), a selective agonist of estrogen receptor β(ERβ), in liver cirrhosis with portal hypertension(PHT) and isolated hepatic stellate cells(HSCs).METHODS: Female Sprague-Dawley rats were ovariectomized(OVX), and liver cirrhosis with PHT was induced by CCl4 injection. DPN and PHTPP, the selective ERβ agonist and antagonist, were used as drug interventions. Liver fibrosis was assessed by hematoxylin and eosin(HE) and Masson's trichrome staining and by analyzing smooth muscle actin expression. Hemodynamic parameters were determined in vivo using colored microspheres technique. Protein expression and phosphorylation were determined by immunohistochemical staining and Western blot analysis. Messenger RNA levels were analyzed by quantitative real-time polymerase chain reaction(q RT-PCR). Collagengel contraction assay was performed using gel lattices containing HSCs treated with DPN, PHTPP, or Y-27632 prior to ET-1 addition. RESULTS: Treatment with DPN in vivo greatly lowered portal pressure and improved hemodynamic parameters without affecting mean arterial pressure, which was associated with the attenuation of liver fibrosis and intrahepatic vascular resistance(IHVR). In CCl4-treated rat livers, DPN significantly decreased the expression of Rho A and ROCK Ⅱ, and even suppressed ROCK Ⅱ activity. Moreover, DPN remarkedly increased the levels of endothelial nitric oxide synthase(e NOS) and phosphorylated e NOS, and promoted the activities of protein kinase G(PKG), which is an NO effector in the liver. Furthermore, DPN reduced the contractility of activated HSCs in the 3-dimensional stress-relaxed collagen lattices, and decreased the ROCK Ⅱ activity in activated HSCs. Finally, in vivo /in vitro experiments demonstrated that MLC activity was inhibited by ***: For OVX rats with liver cirrhosis, DPN suppressed liver Rho A/ROCK signal, facilitated NO/PKG pathways, and decreased IHVR, giving rise to reduced portal pre

关键词： Portal hypertension Estrogen receptor Rho-kinase signaling Nitric oxide Hepatic stellate cells

Hybrid bioartificial liver support in cynomolgus monkeys with D-galactosamine-induced acute liver failure

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World Journal of Gastroenterology 2014年第46期20卷 17399-17406页

作者： zhi Zhang Yi-Chao Zhao Yuan cheng Guo-deng Jian Ming-Xin Pan Yi Gao Second Department of Hepatobiliary Zhujiang HospitalSouthern Medical University Department of Hepatobiliary Tangshan Gongren Hospital Chancheng District Central Hospital Guangdong Province Institute of Regenerative Medicine Zhujiang HospitalSouthern Medical University

AIM: To evaluate a hybrid bioartificial liver support system (HBALSS) in cynomolgus monkeys with acute liver failure.

关键词： Acute liver failure Chinese human liver cells Cynomolgus monkey Human liver cell Hybrid bioartificial liver

Color gradients of the galaxies at 0.5

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Research in Astronomy and Astrophysics 2018年第11期18卷 145-156页

作者： zhi-Xiong Liang cheng Li Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030China University of Chinese Academy of Sciences Beijing 100049China Tsinghua Center for Astrophysics and Physics Department Tsinghua UniversityBeijing 100084China

We investigate the dependence of clustering on luminosity, stellar mass and color gradient for galaxies at 0.5 < z < 1, using a sample of;300 galaxies from the final data release of the VIMOS Public Extragalactic Redshift Survey（VIPERS-PDR2）. We estimate both the auto-correlation function for galaxy samples selected by B-band absolute magnitude and stellar mass, and the cross-correlation function of galaxy samples selected by color gradient with respect to the full galaxy sample. The autocorrelation function amplitudes at fixed scale are found to positively correlate with both galaxy luminosity and stellar mass, and the effect holds for all the scales probed(0.2 h;Mpc < rp< 20 h;Mpc),in good agreement with previous measurements based on an earlier data release of VIPERS. When the stellar mass is limited to a narrow range, we find the clustering power to be essentially independent of galaxy color gradient, and this conclusion is true for all the masses and all the scales considered here. In a parallel paper, we find that the half-light radius is the only galaxy property other than stellar mass that is related to color gradient. Considering the previous finding that clustering depends weakly on galaxy structure at given mass, the non-dependence of clustering on color gradient found here reinforces our conclusion that the color gradient and structural parameters of a galaxy are intrinsically related to each other.

关键词： galaxies: photometry galaxies: statistics galaxies: evolution

Solidification in Soft-Contact Continuous Casting Mold with Alternating Electromagnetic Field

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Journal of Iron and Steel Research International 2003年第1期10卷 15-19页

作者： deng An-yuan HE Ji-cheng Northeastern University

The mechanical behavior of the mushy zone was studied in detail. Based on the analysis of conventional high temperature mechanical model, considering the physical phenomenon in casting process, a mechanical model suitable for describing the mechanical behavior of the casting material in twin roll casting process was built. Comparing experimental results to the numerical simulated ones, the mechanical model was proved to be correct.

关键词： strip casting mushy zone mechanical model constitutive equation