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Water-stable ZIF-300/Ultrason? mixed-matrix membranes for selective CO_2 capture from humid post combustion flue gas

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Chinese Journal of Chemical Engineering 2018年第5期26卷 1012-1021页

作者： Muhammad Sarfraz M. ba-Shammakh Department of Polymer and Process Engineering University of Engineering and Technology Lahore 54890 Pakistan Department of Chemical Engineering King Fahd University of Petroleum and Minerals Dhahran 31261 Saudi Arabia

Water stable mixed-matrix membranes(MMMs) were developed to help control the global warming by capturing and sequestrating carbon dioxide(CO_2) from post-combustion flue gas originated from burning of fossil *** of different compositions were prepared by doping glassy polymer Ultrason? S 6010(US) with nanocrystals of zeolitic imidazolate frameworks(ZIF-300) in varying degrees. Solution-casting technique was used to fabricate various MMMs to optimize their CO_2 capturing performance from both dry and wet gases. The prepared composite membranes indicated enhanced filler-polymer interfacial adhesion, consistent distribution of nanofiller, and thermally established matrix configuration. CO_2 permeability of the membranes was enhanced as demonstrated by gas sorption and permeation experiments performed under both dry and wet conditions. As compared to neat Ultrason? membrane, CO_2 permeability of the composite membrane doped with 40 wt% ZIF-300 nanocrystals was increased by four times without disturbing CO_2/N_2 ideal selectivity. In contrast to majority of previously reported membranes, key features of the fabricated MMMs include their structural stability under humid conditions coupled with better and unaffected gas separation performance.

关键词： Hydrophobic MMMs ZIF-300 Gas permeation CO2 capture Permselectivity

Scattering and diffraction of plane SH-waves by periodically distributed canyons

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Earthquake Engineering and Engineering Vibration 2016年第2期15卷 325-339页

作者： ba Zhenning Liang Jianwen Zhang Yanju Department of Civil Engineering Tianjin University Key Laboratory of Coast Civil Structure Safety (Tianjin University) Ministry of Education

A new method is presented to study the scattering and diffraction of plane SH-waves by periodically distributed canyons in a layered half-space. This method uses the indirect boundary element method combined with Green＇s functions of uniformly distributed loads acting on periodically distributed inclined lines. The periodicity feature of the canyons is exploited to limit the discretization effort to a single canyon, which avoids errors induced by the truncation of the infinite boundary, and the computational complexity and the demand on memory can be significantly reduced. Furthermore, the total wave fields are decomposed into the free field and scattered field in the process of calculation, which means that the method has definite physical meaning. The implementation of the method is described in detail and its accuracy is verified. Parametric studies are performed in the frequency domain by taking periodically distributed canyons of semi-circular and semi-elliptic cross-sections as examples. Numerical results show that the dynamic responses of periodically distributed canyons can be quite different from those for a single canyon and significant dynamic interactions exist between the canyons.

关键词： periodically layered uniformly verified decomposed truncation elliptic discretization scattered circular

Spatial analysis and structure of a cross-timber stand in the TallGrass Prairie Preserve (Pawhuska, Oklahoma)

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Journal of Forestry Research 2013年第1期24卷 47-52页

作者： José Ramón arévalo Departamento de Ecología Facultad de BiologíaUniversidad de La LagunaLa Laguna 38206Spain

I analyzed the spatial distribution and structure of trees in a cross timber forest in the Tallgrass Prairie Preserve （Pawhuska, Oklahoma, USA）. I mapped and measured diameter of all stems, saplings （〉1.5 m tall） and dead trees in a 4-ha plot. The stand was dominated by Quercus stellata and Q. marilandica. In total, I mapped 7,636 trees, consisting of 6,785 Q. stellata, 846 Q. marilandica, 2 Celtis occidentalis, 1 Fraxinus pensilvanica and 2 Prunus americana. For saplings, I mapped 54 Q. stellata and 21 Q. marilandica. The size class distribution of the two dominant species did not differ. The dominant mortality class was “standing dead”, while I only found saplings less than 2 m tall. The spatial distribution of the species indicated segregation in the use of the environment, generating a clumped univariate distribution of stems of the same species within radii of 30 m, but repulsion outside 30 m. This segregation can be explained by the different ecological requirements of each species.

关键词： conservation point pattern analysis Quercus stellata Q.marilandica size class distribution

Regularity of Structural Superplasticity of Hypoeutectoid Steel

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Journal of Iron and Steel Research International 2005年第4期12卷 60-62页

作者： YANGYun-lin WENJiu-ba HenanUniversityofScienceandTechnology Henan471003China

The curve of the relation between fracture elongation and temperature for unltrafine grained low alloy hypoeutectoid steels generally shows that three peaks occur at temperatures just below A_ c1, between A_ c1 and A_ c3, and just above A_ c3, When these steels are subjected to superplastic tensile test at different temperatures, the value of the last one is the lowest and the other two peaks are different one from another depending on components, microstructures and deformation conditions of the steels.

关键词： hypoeutectoid steel structural superplasticity superplastic temperature

Treatment strategies for patients with HER2-positive gastric cancer

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Cancer Biology & Medicine 2023年第12期20卷 934-941页

作者： Feixue Wang Yi ba Department of Medical Oncology Department of Cancer CenterPeking Union Medical College HospitalChinese Academy of Medical SciencesBeijing 100032China Department of GI Medical Oncology Tianjin Medical University Cancer Institute&HospitalNational Clinical Research Center for CancerTianjin’s Clinical Research Center for CancerTianjin Key Laboratory of Digestive CancerKey Laboratory of Cancer Prevention and TherapyTianjin 300060China

Gastric cancer (GC) is a major health concern globally,ranking fifth in frequency and fourth in cancer-associated *** China,an estimated 396,500 new cases are diagnosed each year,and late-stage disease comprises more than 80%of *** of late diagnosis and heterogeneous characteristics,the prognosis of GC remains *** patients with advanced disease,traditional chemotherapy has been the mainstay of treatment,but its clinical outcomes are far from satisfactory,with a 5-year survival rate below 10%.

关键词： patients cancer Gastric

Microstructure and Property Relationships in Resistance Spot Weld between 7114 Interstitial Free Steel and 304 Austenitic Stainless Steel

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Journal of Materials Science & Technology 2006年第3期22卷 375-381页

作者： Ahmet Hasanba■o■lu Ramazan Kaar Department of Metal Education Karabük Technical Education Faculty Karabük 78100 Turkey

Due to the differences in physical, chemical and mechanical properties of the base metals, the resistance spot welding of dissimilar materials is generally more challenging than that of similar materials. The influence of the primary welding parameters affecting the heat input such as peak current on the morphology, microhardness, and tensile shear load bearing capacity of dissimilar welds between 304 grades austenitic and 7114 grade interstitial free steel has been investigated in this study. The optimum welding parameters producing maximum joint strength were established at a peak current of 9 kA, where the electrode force is kept 6×10^-5 Pa and weld time is kept constant 17 cycles, respectively. The primary cause of weakening the weldment is identified as the excessive grain growing region of heat affected zone （HAZ） in case of 7114 grade interstitial free steel.

关键词： Resistance spot weld Interstitial free steel Austenitic stainless steel

Characterization and antifouling activity analysis of extracellular polymeric substances produced by an epibiotic bacterial strain Kocuria flava associated with the green macroalga Ulva lactuca

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Acta Oceanologica Sinica 2021年第4期40卷 107-115页

作者： Mohammad Abdulaziz ba-akdah Sathianeson Satheesh Department of Marine Biology Faculty of Marine SciencesKing Abdulaziz UniversityJeddah 21589Saudi Arabia

Extracellular polymeric substances(EPS)are present externally to the microorganisms and play an important role in attachment and biofilm *** polymers possess antibacterial and antifouling *** this study,the antifouling activity of EPS produced by an epibiotic bacterium associated with macroalga Ulva lactuca was assessed against fouling bacteria and barnacle *** indicate that the EPS isolated from the epibiotic bacterium inhibits the biofilm formation of the bacteria without much antibacterial ***,the EPS reduced the settlement of barnacle larvae on the hard substrate under laboratory *** epibiotic bacterium was identified as Kocuria flava based on 16 S rRNA gene *** EPS was further analysed using Fourier transform infrared(FT-IR),nuclear magnetic resonance(NMR)and X-ray diffraction(XRD)to understand the biochemical *** analysis revealed the presence of polysaccharides,proteins,acetyl amine and succinyl *** electron microscope analysis indicated that the EPS consisted of aggregated and irregular sphere-shaped particles.

关键词： biofouling antifouling Kocuria flava exopolymers antibiofilm activity Red Sea

Palladium-induced electron-transfer reaction of difluorodiiodomethane with alkenes

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Chinese Journal of Chemistry 1996年第6期14卷 549-554页

作者： Li, ar Chen, QY CHINESE ACAD SCI SHANGHAI INST ORGAN CHEMSHANGHAI 200032PEOPLES R CHINA

The addition reaction of difluorodiiodomethane (1) with alkenes in the presence of PdCl2(PPh(3))(2) or Pd(PPh(3))(4) afforded the corresponding iododifluoromethylated compounds in excellent yield.

关键词： difluorodiiodomethane alkenes palladium complex

High-Efficiency DC-DC Converter for Large Input-Voltage Fluctuations in Solar Applications

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Chinese Journal of Electronics 2015年第3期24卷 502-507页

作者： AGUILLON-GarCIA Jacobo baNUELOS-SANCHEZ Pedro SIST Sun Yat-sen University

In the solar energy systems the solar irradiance variation is partially engaged, limiting the converter’s transformation rate for a certain input amount and leaving the rest of energy unconverted. In order to utilize at its maximum the energy provided from a Photovoltaic(PVP) system, this manuscript proposed a topology that can cope with marginal input voltage variations from 60V(DC) up to 1050V(DC) for a steady output voltage of 700V(DC). This output voltage value is suitable for any interlink post-regulation architecture. based on previous observations, this paper presents a wide-input voltage high-efficiency non-isolated single-control topology. Analysis, operating stages, simulations and experimental results for a 3k W prototype are presented.

关键词： DC-DC power converters Energy conversion Photovoltaic system Power conditioning Solar generation